xtd::drawing::image Class Reference

Inheritance diagram for xtd::drawing::image:

Definition

An abstract base class that provides functionality for the bitmap and metafile descended classes.

class drawing_export_ image : public xtd::object, public xtd::iequatable<image>

Inheritance

xtd::object → xtd::drawing::image

Namespace

xtd::drawing

Library

xtd.drawing

Remarks

To draw an image on a Windows Form, you should use one of the draw_image methods.

Examples

draw_image.cpp, image_converter.cpp, and toggle_button2.cpp.

Public Fields
static image	empty
	Represent an empty xtd::drawing::image.

Public Properties
int32	flags () const noexcept
	Gets attribute flags for the pixel data of this xtd::drawing::image.
std::vector< guid >	frame_dimentions_list () const noexcept
	Gets an array of GUIDs that represent the dimensions of frames within this image.
intptr	handle () const noexcept
	Gets the handle of this image.
int32	height () const noexcept
	Gets the height, in pixels, of this image.
float	horizontal_resolution () const noexcept
	Gets the horizontal resolution, in pixels per inch, of this image.
imaging::color_palette	palette () const noexcept
	Gets the color palette used for this image.
void	palette (const imaging::color_palette &palette) noexcept
	Sets the color palette used for this image.
const size_f &	physical_dimension () const noexcept
	Gets the width and height of this image.
imaging::pixel_format	pixel_format () const noexcept
	Gets the pixel format for this image.
const std::vector< int32 > &	property_id_list () const noexcept
	Gets IDs of the property items stored in this image.
const std::vector< imaging::property_item > &	property_items () const noexcept
	Gets all the property items (pieces of metadata) stored in this image.
const imaging::image_format &	raw_format () const noexcept
	Gets the file format of this image.
const drawing::size &	size () const noexcept
	Gets the width and height, in pixels, of this image.
const std::any &	tag () const noexcept
	Gets an object that provides additional data about the image.
void	tag (const std::any &tag) noexcept
	Sets an object that provides additional data about the image.
float	vertical_resolution () const noexcept
	Gets the vertical resolution, in pixels per inch, of this image.
int32	width () const noexcept
	Gets the width, in pixels, of this image.

Public Methods
image	clone () const
	Creates an exact copy of this xtd::drawing::image.
graphics	create_graphics ()
	Creates the xtd::drawing::graphics for the image.
bool	equals (const image &image) const noexcept override
const xtd::byte *	get_alpha () const
	Gets the image alpha pointer, which represents the alpha data of the image.
xtd::byte *	get_alpha ()
	Gets the image alpha pointer, which represents the alpha data of the image.
xtd::drawing::rectangle_f	get_bounds (xtd::drawing::graphics_unit page_unit) const noexcept
	Gets the bounds of the image in the specified unit.
xtd::drawing::imaging::encoder_parameters	get_encoder_parameter_list (xtd::guid encoder) const noexcept
	Returns information about the parameters supported by the specified image encoder.
size_t	get_frame_count (const xtd::drawing::imaging::frame_dimension &dimension) const
	Returns the number of frames of the specified dimension.
xtd::drawing::imaging::property_item	get_property_item (int32 propid)
	Gets the specified property item from this xtd::drawing::image.
const xtd::byte *	get_rgb () const
	Gets the image data pointer, which represents the RGB data of the image.
xtd::byte *	get_rgb ()
	Gets the image data pointer, which represents the RGB data of the image.
xtd::drawing::image	get_thmbnail_image (int32 thumb_width, int32 thunb_height) noexcept
	Returns a thumbnail for this xtd::drawing::image.
void	rotate_flip (xtd::drawing::rotate_flip_type rotate_flip_type)
	Rotates, flips, or rotates and flips the xtd::drawing::image.
void	save (const xtd::string &filename) const
	Saves this xtd::drawing::image to the specified file or stream.
void	save (const xtd::string &filename, const xtd::drawing::imaging::image_format &format) const
	Saves this xtd::drawing::image to the specified file in the specified format.
void	save (std::ostream &stream, const xtd::drawing::imaging::image_format &format) const
	Saves this image to the specified stream in the specified format.
virtual bool	equals (const object &obj) const noexcept
	Determines whether the specified object is equal to the current object.
template<typename object_a_t , typename object_b_t >
static bool	equals (const object_a_t &object_a, const object_b_t &object_b) noexcept
	Determines whether the specified object instances are considered equal.

Public Static Methods
static image	from_file (const xtd::string &filename)
	Creates an image from the specified file.
static bitmap	from_hbitmap (intptr hbitmap)
	Creates a xtd::drawing::bitmap from a handle to a GDI bitmap.
static image	from_stream (std::istream &stream)
	Creates an xtd::drawing::image from the specified data stream.
static image	from_data (const char *const *bits)
	Creates an xtd::drawing::image from the specified data pointer.
static int32	get_pixel_format_size (xtd::drawing::imaging::pixel_format pixfmt) noexcept
	Returns the color depth, in number of bits per pixel, of the specified pixel format.
static bool	is_alpha_pixel_format (xtd::drawing::imaging::pixel_format pixfmt) noexcept
	Returns a value that indicates whether the pixel format for this xtd::drawing::image contains alpha information.
static bool	is_canonical_pixel_format (xtd::drawing::imaging::pixel_format pixfmt) noexcept
	Returns a value that indicates whether the pixel format is 32 bits per pixel.
static bool	is_extended_pixel_format (xtd::drawing::imaging::pixel_format pixfmt) noexcept
	Returns a value that indicates whether the pixel format is 64 bits per pixel.

Additional Inherited Members
Public Member Functions inherited from xtd::object
	object ()=default
	Create a new instance of the ultimate base class object.
virtual size_t	get_hash_code () const noexcept
	Serves as a hash function for a particular type.
virtual type_object	get_type () const noexcept
	Gets the type of the current instance.
template<typename object_t >
xtd::uptr< object_t >	memberwise_clone () const
	Creates a shallow copy of the current object.
virtual xtd::string	to_string () const noexcept
	Returns a xtd::string that represents the current object.
Public Member Functions inherited from xtd::iequatable< image >
virtual bool	equals (const image &) const noexcept=0
	Indicates whether the current object is equal to another object of the same type.
Static Public Member Functions inherited from xtd::object
template<typename object_a_t , typename object_b_t >
static bool	equals (const object_a_t &object_a, const object_b_t &object_b) noexcept
	Determines whether the specified object instances are considered equal.
template<typename object_a_t , typename object_b_t >
static bool	reference_equals (const object_a_t &object_a, const object_b_t &object_b) noexcept
	Determines whether the specified object instances are the same instance.

Member Function Documentation

flags()

int32 xtd::drawing::image::flags ( ) const

noexcept

Gets attribute flags for the pixel data of this xtd::drawing::image.

Returns

The integer representing a bitwise combination of xtd::drawing::imaging::image_flags for this xtd::drawing::image.

Remarks

The integer value returned from this method will correspond to a sum of image_flags, as described in the following table.

image_flag value	Integer representation
image_flags_none	0
Iimage_flags_scalable	1
Iimage_flags_has_alpha	2
Iimage_flags_has_translucent	4
Iimage_flags_partially_scalable	8
Iimage_flags_color_space_rgb	16
Iimage_flags_color_space_cmyk	32
Iimage_flags_color_space_gray	64
Iimage_flags_color_space_ycbr	128
Iimage_flags_color_space_ycck	256
Iimage_flags_has_real_dpi	4096
Iimage_flags_has_real_pixel_size	8192
Iimage_flags_read_only	65536
Iimage_flags_caching	131072

For example, if the Flags property for an image returned 77960, the image_flags for the image would be read_only, has_real_dpi, has_real_pixel_size, color_space_ycbcr, and partially_scalable.

frame_dimentions_list()

std::vector< guid > xtd::drawing::image::frame_dimentions_list ( ) const

noexcept

Gets an array of GUIDs that represent the dimensions of frames within this image.

Returns

An array of GUIDs that specify the dimensions of frames within this xtd::drawing::image from most significant to least significant.

Remarks

This method returns information about multiple-frame images, which come in two styles: multiple page and multiple resolution.

A multiple-page image is an image that contains more than one image. Each page contains a single image (or frame). These pages (or images, or frames) are typically displayed in succession to produce an animated sequence, such as an animated .gif file.

A multiple-resolution image is an image that contains more than one copy of an image at different resolutions. This is commonly used by MIP mapping where the displayed image size determines the resolution of the image used for drawing. GDI+ can support an arbitrary number of pages (or images, or frames), as well as an arbitrary number of resolutions. The defined dimensions are properties of the frame_dimension.

handle()

intptr xtd::drawing::image::handle ( ) const

noexcept

Gets the handle of this image.

Returns

The handle of this image.

height()

int32 xtd::drawing::image::height ( ) const

noexcept

Gets the height, in pixels, of this image.

Returns

The height, in pixels, of this image.

Examples

painting.cpp.

horizontal_resolution()

float xtd::drawing::image::horizontal_resolution ( ) const

noexcept

Gets the horizontal resolution, in pixels per inch, of this image.

Returns

The horizontal resolution, in pixels per inch, of this image.

palette() [1/2]

imaging::color_palette xtd::drawing::image::palette ( ) const

noexcept

Gets the color palette used for this image.

Returns

An xtd::drawing::imaging::color_palette that represents the color palette used for this image.

Remarks

This property returns a copy of the xtd::drawing::imaging::color_palette object used by this xtd::drawing::image.

palette() [2/2]

void xtd::drawing::image::palette ( const imaging::color_palette &  palette )

noexcept

Sets the color palette used for this image.

Parameters

palette

A color_palette that represents the color palette used for this image.

physical_dimension()

const size_f & xtd::drawing::image::physical_dimension ( ) const

noexcept

Gets the width and height of this image.

Returns

A xtd::drawing::size_f structure that represents the width and height of this image.

Remarks

If the image is a bitmap, the width and height are returned in pixels. If the image is a metafile, the width and height are returned in 0.01 millimeter units.

pixel_format()

imaging::pixel_format xtd::drawing::image::pixel_format ( ) const

noexcept

Gets the pixel format for this image.

Returns

A pixel_format that represents the pixel format for this image.

property_id_list()

const std::vector< int32 > & xtd::drawing::image::property_id_list ( ) const

noexcept

Gets IDs of the property items stored in this image.

Returns

An array of the property IDs, one for each property item stored in this image.

Remarks

If the image has no property items or if the image format does not support property items, the property_id_list property returns an empty array (that is, an array of length zero).

property_items()

const std::vector< imaging::property_item > & xtd::drawing::image::property_items ( ) const

noexcept

Gets all the property items (pieces of metadata) stored in this image.

Returns

An array of xtd::drawing::imaging::property_item objects, one for each property item stored in the image.

Remarks

IIf the image has no property items or if the image format does not support property items, property_items returns an empty array (that is, an array of length zero).

raw_format()

const imaging::image_format & xtd::drawing::image::raw_format ( ) const

noexcept

Gets the file format of this image.

Returns

The image_format that represents the file format of this image.

size()

const drawing::size & xtd::drawing::image::size ( ) const

noexcept

Gets the width and height, in pixels, of this image.

Returns

A size structure that represents the width and height, in pixels, of this image.

Examples

painting.cpp.

tag() [1/2]

const std::any & xtd::drawing::image::tag ( ) const

noexcept

Gets an object that provides additional data about the image.

Returns

The object that provides additional data about the image.

tag() [2/2]

void xtd::drawing::image::tag ( const std::any &  tag )

noexcept

Sets an object that provides additional data about the image.

Parameters

tag	The object that provides additional data about the image.

vertical_resolution()

float xtd::drawing::image::vertical_resolution ( ) const

noexcept

Gets the vertical resolution, in pixels per inch, of this image.

Returns

The vertical resolution, in pixels per inch, of this image.

width()

int32 xtd::drawing::image::width ( ) const

noexcept

Gets the width, in pixels, of this image.

Returns

The width, in pixels, of this image.

Examples

painting.cpp, and screenshot.cpp.

clone()

image xtd::drawing::image::clone

(

)

const

Creates an exact copy of this xtd::drawing::image.

Returns

The xtd::drawing::image this method creates.

create_graphics()

graphics xtd::drawing::image::create_graphics

(

)

Creates the xtd::drawing::graphics for the image.

Returns

A xtd::drawing::graphics for the image.

get_alpha() [1/2]

const xtd::byte * xtd::drawing::image::get_alpha

(

)

const

Gets the image alpha pointer, which represents the alpha data of the image.

Returns

The pointer or alpha image.

Remarks

The size of this data is 1 byte (alpha) * height() * width().

If the image has no handle, such as an empty image, this method returns nullptr.

Warning

Be careful when using this pointer as there is no control and you can exceed its size and create irreparable problems.

Remarks

To access the position of a specific pixel, it's best to use the xtd::drawing::image::get_pixel and xtd::drawing::image::set_pixel methods.

get_alpha() [2/2]

xtd::byte * xtd::drawing::image::get_alpha

(

)

Gets the image alpha pointer, which represents the alpha data of the image.

Returns

The pointer or alpha image.

Remarks

The size of this data is 1 byte (alpha) * height() * width().

If the image has no handle, such as an empty image, this method returns nullptr.

Warning

Be careful when using this pointer as there is no control and you can exceed its size and create irreparable problems.

Remarks

To access the position of a specific pixel, it's best to use the xtd::drawing::image::get_pixel and xtd::drawing::image::set_pixel methods.

get_bounds()

xtd::drawing::rectangle_f xtd::drawing::image::get_bounds ( xtd::drawing::graphics_unit  page_unit ) const

noexcept

Gets the bounds of the image in the specified unit.

Parameters

page_unit

One of the xtd::drawing::graphics_unit values indicating the unit of measure for the bounding rectangle.

Returns

The xtd::drawing::rectangle_f that represents the bounds of the image, in the specified unit.

get_encoder_parameter_list()

xtd::drawing::imaging::encoder_parameters xtd::drawing::image::get_encoder_parameter_list ( xtd::guid  encoder ) const

noexcept

Returns information about the parameters supported by the specified image encoder.

Parameters

guid	A GUID that specifies the image encoder.

Returns

An xtd::drawing::imaging::encoder_parameters that contains an array of xtd::drawing::imaging::encoder_parameter objects. Each xtd::drawing::imaging::encoder_parameter contains information about one of the parameters supported by the specified image encoder.

get_frame_count()

size_t xtd::drawing::image::get_frame_count

(

const xtd::drawing::imaging::frame_dimension &

dimension

)

const

Returns the number of frames of the specified dimension.

Parameters

dimension

A xtd::drawing::imaging::frame_dimension that specifies the identity of the dimension type.

Returns

The number of frames in the specified dimension.

Remarks

This method returns information about multiple-frame images, which come in two styles: multiple page and multiple resolution.

A multiple-page image is an image that contains more than one image. Each page contains a single image (or frame). These pages (or images, or frames) are typically displayed in succession to produce an animated sequence, such as an animated .gif file.

A multiple-resolution image is an image that contains more than one copy of an image at different resolutions. This is commonly used by MIP mapping where the displayed image size determines the resolution of the image used for drawing. GDI+ can support an arbitrary number of pages (or images, or frames), as well as an arbitrary number of resolutions. The defined dimensions are properties of the xtd::drawing::imaging::frame_dimension.

get_property_item()

xtd::drawing::imaging::property_item xtd::drawing::image::get_property_item

(

int32

propid

)

Gets the specified property item from this xtd::drawing::image.

Parameters

propid

The ID of the property item to get.

Returns

The xtd::drawing::imaging::property_item this method gets.

Exceptions

xtd::argument_exception

The image format of this image does not support property items.

Remarks

For a list of property item IDs and links to more information, see Id.

It is difficult to set property items, because the xtd::drawing::imaging::property_item class has no public constructors. One way to work around this restriction is to obtain a xtd::drawing::imaging::property_item by retrieving the xtd::drawing::image::property_item property value or calling the xtd::drawing::image::get_property_item method of an xtd::drawing::image that already has property items. Then you can set the fields of the xtd::drawing::imaging::property_item and pass it to xtd::drawing::image::set_property_item.

get_rgb() [1/2]

const xtd::byte * xtd::drawing::image::get_rgb

(

)

const

Gets the image data pointer, which represents the RGB data of the image.

Returns

The pointer or data image.

Remarks

This is most often used when doing direct image manipulation. The return value points to an array of characters in RGBRGBRGB... format in the top-to-bottom, left-to-right order, that is the first RGB triplet corresponds to the first pixel of the first row, the second one — to the second pixel of the first row and so on until the end of the first row, with second row following after it and so on.

The size of this data is 3 bytes (RGB) * height() * width().

If the image has no handle, such as an empty image, this method returns nullptr.

Warning

Be careful when using this pointer as there is no control and you can exceed its size and create irreparable problems.

Remarks

To access the position of a specific pixel, it's best to use the xtd::drawing::image::get_pixel and xtd::drawing::image::set_pixel methods.

get_rgb() [2/2]

xtd::byte * xtd::drawing::image::get_rgb

(

)

Gets the image data pointer, which represents the RGB data of the image.

Returns

The pointer or data image.

Remarks

This is most often used when doing direct image manipulation. The return value points to an array of characters in RGBRGBRGB... format in the top-to-bottom, left-to-right order, that is the first RGB triplet corresponds to the first pixel of the first row, the second one — to the second pixel of the first row and so on until the end of the first row, with second row following after it and so on.

The size of this data is 3 bytes (RGB) * height() * width().

If the image has no handle, such as an empty image, this method returns nullptr.

Warning

Be careful when using this pointer as there is no control and you can exceed its size and create irreparable problems.

Remarks

To access the position of a specific pixel, it's best to use the xtd::drawing::image::get_pixel and xtd::drawing::image::set_pixel methods.

get_thmbnail_image()

xtd::drawing::image xtd::drawing::image::get_thmbnail_image ( int32  thumb_width, int32  thunb_height  )

noexcept

Returns a thumbnail for this xtd::drawing::image.

Parameters

thbmb_width	The width, in pixels, of the requested thumbnail image.
thum_height	The height, in pixels, of the requested thumbnail image.

Returns

An xtd::drawing::image that represents the thumbnail.

Remarks

If the xtd::drawing::image contains an embedded thumbnail image, this method retrieves the embedded thumbnail and scales it to the requested size. If the xtd::drawing::image does not contain an embedded thumbnail image, this method creates a thumbnail image by scaling the main image.

The xtd::drawing::image::get_thumbnail_image method works well when the requested thumbnail image has a size of about 120 x 120 pixels. If you request a large thumbnail image (for example, 300 x 300) from an xtd::drawing::image that has an embedded thumbnail, there could be a noticeable loss of quality in the thumbnail image. It might be better to scale the main image (instead of scaling the embedded thumbnail) by calling the xtd::drawing::graphics::draw_image method.

rotate_flip()

void xtd::drawing::image::rotate_flip

(

xtd::drawing::rotate_flip_type

rotate_flip_type

)

Rotates, flips, or rotates and flips the xtd::drawing::image.

Parameters

rotate_flip_type

A xtd::drawing::rotate_flip_type member that specifies the type of rotation and flip to apply to the image.

Remarks

The xtd::drawing::image::rotate_flip method rotates the image clockwise.

If you wish to draw on an image once it has been rotated, you should always retrieve a new graphics object from the image, otherwise an exception could occur.

save() [1/3]

void xtd::drawing::image::save

(

const xtd::string &

filename

)

const

Saves this xtd::drawing::image to the specified file or stream.

Parameters

filename

A string that contains the name of the file to which to save this xtd::drawing::image.

Remarks

If no encoder exists for the file format of the image, the Portable Network Graphics (PNG) encoder is used. When you use the xtd::drawing::image::save method to save a graphic image as a Windows Metafile Format (WMF) or Enhanced Metafile Format (EMF) file, the resulting file is saved as a Portable Network Graphics (PNG) file. This behavior occurs because the GDI+ component of the .NET Framework does not have an encoder that you can use to save files as .wmf or .emf files.

Saving the image to the same file it was constructed from is not allowed and throws an exception.

Examples

image_xpm.cpp.

save() [2/3]

void xtd::drawing::image::save	(	const xtd::string &	filename,
		const xtd::drawing::imaging::image_format &	format
	)		const

Saves this xtd::drawing::image to the specified file in the specified format.

Parameters

filename	A string that contains the name of the file to which to save this xtd::drawing::image.
format	The xtd::drawing::imaging::image_format for this xtd::drawing::image.

save() [3/3]

void xtd::drawing::image::save	(	std::ostream &	stream,
		const xtd::drawing::imaging::image_format &	format
	)		const

Saves this image to the specified stream in the specified format.

Parameters

stream	The std::otream where the image will be saved.
format	The xtd::drawing::imaging::image_format for this xtd::drawing::image.

Remarks

You should avoid saving an image to the same stream that was used to construct it. Doing so might damage the stream.

The image must be saved to the stream at an offset of zero. If any additional data has been written to the stream before saving the image, the image data in the stream will be corrupted.

from_file()

static image xtd::drawing::image::from_file ( const xtd::string &  filename )

inlinestatic

Creates an image from the specified file.

Parameters

filename

A string that contains the name of the file from which to create the image.

Returns

The xtd::drawing::image this method creates.

from_hbitmap()

static bitmap xtd::drawing::image::from_hbitmap ( intptr  hbitmap )

static

Creates a xtd::drawing::bitmap from a handle to a GDI bitmap.

Parameters

hbitmap

The GDI bitmap handle from which to create the xtd::drawing::bitmap.

Returns

The xtd::drawing::bitmap this method creates.

Remarks

The xtd::drawing::image::from_hbitmap method makes a copy of the GDI bitmap; so you can release the incoming GDI bitmap using the GDI DeleteObject method immediately after creating the new xtd::drawing::image.

from_stream()

static image xtd::drawing::image::from_stream ( std::istream &  stream )

static

Creates an xtd::drawing::image from the specified data stream.

Parameters

stream

A std::istream that contains the data for this xtd::drawing::image.

Returns

The xtd::drawing::image this method creates.

Remarks

You must keep the stream open for the lifetime of the xtd::drawing::image.

Note

The xtd::drawing::image class does not support alpha transparency in bitmaps. To enable alpha transparency, use PNG images with 32 bits per pixel.

from_data()

static image xtd::drawing::image::from_data ( const char *const *  bits )

static

Creates an xtd::drawing::image from the specified data pointer.

Parameters

data	A pointer that contains the data for this xtd::drawing::image.

Returns

The xtd::drawing::image this method creates.

Remarks

This method is used for creating a xtd::drawing::image from an XPM (or XBM) image.

get_pixel_format_size()

static int32 xtd::drawing::image::get_pixel_format_size ( xtd::drawing::imaging::pixel_format  pixfmt )

staticnoexcept

Returns the color depth, in number of bits per pixel, of the specified pixel format.

Parameters

pixfmt

The xtd::drawing::imaging::pixel_format member that specifies the format for which to find the size.

Returns

The color depth of the specified pixel format.

is_alpha_pixel_format()

static bool xtd::drawing::image::is_alpha_pixel_format ( xtd::drawing::imaging::pixel_format  pixfmt )

staticnoexcept

Returns a value that indicates whether the pixel format for this xtd::drawing::image contains alpha information.

Parameters

pixfmt

The PixelFormat to test.

Returns

true if pixfmt contains alpha information; otherwise, false.

is_canonical_pixel_format()

static bool xtd::drawing::image::is_canonical_pixel_format ( xtd::drawing::imaging::pixel_format  pixfmt )

staticnoexcept

Returns a value that indicates whether the pixel format is 32 bits per pixel.

Parameters

pixfmt

The PixelFormat to test.

Returns

true if pixfmt is canonical; otherwise, false.

is_extended_pixel_format()

static bool xtd::drawing::image::is_extended_pixel_format ( xtd::drawing::imaging::pixel_format  pixfmt )

staticnoexcept

Returns a value that indicates whether the pixel format is 64 bits per pixel.

Parameters

pixfmt

The PixelFormat to test.

Returns

true if pixfmt is extended; otherwise, false.

equals() [1/2]

virtual bool xtd::object::equals ( const object &  obj ) const

virtualnoexcept

Determines whether the specified object is equal to the current object.

Parameters

obj	The object to compare with the current object.

Returns

true if the specified object is equal to the current object. otherwise, false.

Examples

The following code example compares the current instance with another object.

#include <xtd/console>
 
using namespace xtd;
 
auto main() -> int {
  auto object1 = new_ptr<object>();
  auto object2 = new_ptr<object>();
  
  auto object3 = object2;
  console::write_line(object1->equals(*object3));
  console::write_line(*object1 == *object3);
  object3 = object1;
  console::write_line(object1->equals(*object3));
  console::write_line(*object1 == *object3);
}
 
// This code produces the following output :
//
// false
// false
// true
// true

Reimplemented from xtd::object.

equals() [2/2]

template<typename object_a_t , typename object_b_t >

static bool xtd::object::equals ( const object_a_t &  object_a, const object_b_t &  object_b  )

inlinestaticnoexcept

Determines whether the specified object instances are considered equal.

Parameters

object_a	The first object to compare.
object_b	The second object to compare.

Returns

true if object_a is the same instance as object_b or if both are null references or if object_a(object_b) returns true. otherwise, false.

Examples

The following code example compares different objects.

#include <xtd/console>
 
using namespace xtd;
 
auto main() -> int {
  string s1 = "Tom";
  string s2 = "Carol";
  console::write_line("object::equals(\"{0}\", \"{1}\") => {2}", s1, s2, object::equals(s1, s2));
  
  s1 = "Tom";
  s2 = "Tom";
  console::write_line("object::equals(\"{0}\", \"{1}\") => {2}", s1, s2, object::equals(s1, s2));
  
  s1 = "";
  s2 = "Tom";
  console::write_line("object::equals(\"{0}\", \"{1}\") => {2}", s1, s2, object::equals(s1, s2));
  
  s1 = "Carol";
  s2 = "";
  console::write_line("object::equals(\"{0}\", \"{1}\") => {2}", s1, s2, object::equals(s1, s2));
  
  s1 = "";
  s2 = "";
  console::write_line("object::equals(\"{0}\", \"{1}\") => {2}", s1, s2, object::equals(s1, s2));
}
 
// This code produces the following output :
//
// object::equals("Tom", "Carol") => false
// object::equals("Tom", "Tom") => true
// object::equals("", "Tom") => false
// object::equals("Carol", "") => false
// object::equals("", "") => true

Member Data Documentation

empty

image xtd::drawing::image::empty

static

Represent an empty xtd::drawing::image.

Examples

button_appearance.cpp, button_renderer.cpp, check_box_appearance.cpp, check_box_renderer.cpp, and radio_button_renderer.cpp.

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The documentation for this class was generated from the following file:

• xtd.drawing/include/xtd/drawing/image.h