LoadImageW function (winuser.h)

Article
11/20/2024

Loads an icon, cursor, animated cursor, or bitmap.

Syntax

HANDLE LoadImageW(
  [in, optional] HINSTANCE hInst,
  [in]           LPCWSTR   name,
  [in]           UINT      type,
  [in]           int       cx,
  [in]           int       cy,
  [in]           UINT      fuLoad
);

Parameters

[in, optional] hInst

Type: HINSTANCE

A handle to the module of either a DLL or executable (.exe) that contains the image to be loaded. For more information, see GetModuleHandle. Note that as of 32-bit Windows, an instance handle (HINSTANCE), such as the application instance handle exposed by system function call of WinMain, and a module handle (HMODULE) are the same thing.

To load a predefined image or a standalone resource (icon, cursor, or bitmap file), set this parameter to NULL.

[in] name

Type: LPCTSTR

The image to be loaded.

If the hInst parameter is non-NULL and the fuLoad parameter omits LR_LOADFROMFILE, name specifies the image resource in the hInst module.

If the image resource is to be loaded by name from the module, the name parameter is a pointer to a null-terminated string that contains the name of the image resource.

If the image resource is to be loaded by ordinal from the module, use the MAKEINTRESOURCE macro to convert the image ordinal into a form that can be passed to the LoadImage function.

If the hInst parameter is NULL and the fuLoad parameter omits the LR_LOADFROMFILE value and includes the LR_SHARED, the name specifies the predefined image to load.

The predefined image identifiers are defined in Winuser.h and have the following prefixes:

Prefix	Meaning
OBM_	OEM bitmaps. Use the MAKEINTRESOURCE macro to pass these.
OIC_	OEM icons. Use the MAKEINTRESOURCE macro to pass these.
OCR_	OEM cursors. Use the MAKEINTRESOURCE macro to pass these.
IDI_	Standard icons
IDC_	Standard cursors

To pass OEM image identifiers constants to the LoadImage function, use the MAKEINTRESOURCE macro. For example, to load the OCR_NORMAL cursor, pass MAKEINTRESOURCE(OCR_NORMAL) as the name parameter, NULL as the hInst parameter, and LR_SHARED as one of the flags to the fuLoad parameter.

If the hInst parameter is NULL and the fuLoad parameter includes the LR_LOADFROMFILE value, name is the name of the file that contains the standalone resource (icon, cursor, or bitmap file), - for example, c:\myicon.ico.

For more information, see the Remarks section below.

[in] type

Type: UINT

The type of image to be loaded.

This parameter can be one of the following values:

Value	Meaning
IMAGE_BITMAP	Loads a bitmap.
IMAGE_CURSOR	Loads a cursor.
IMAGE_ICON	Loads an icon.

[in] cx

Type: int

The width, in pixels, of the icon or cursor. If this parameter is zero and the fuLoad parameter is LR_DEFAULTSIZE, the function uses the SM_CXICON or SM_CXCURSOR system metric value to set the width. If this parameter is zero and LR_DEFAULTSIZE is not used, the function uses the actual resource width.

[in] cy

Type: int

The height, in pixels, of the icon or cursor. If this parameter is zero and the fuLoad parameter is LR_DEFAULTSIZE, the function uses the SM_CYICON or SM_CYCURSOR system metric value to set the height. If this parameter is zero and LR_DEFAULTSIZE is not used, the function uses the actual resource height.

[in] fuLoad

Type: UINT

This parameter can be one or more of the following values.

Value	Meaning
LR_CREATEDIBSECTION 0x00002000	When the uType parameter specifies IMAGE_BITMAP, causes the function to return a DIB section bitmap rather than a compatible bitmap. This flag is useful for loading a bitmap without mapping it to the colors of the display device.
LR_DEFAULTCOLOR 0x00000000	The default flag; it does nothing. All it means is "not LR_MONOCHROME".
LR_DEFAULTSIZE 0x00000040	Uses the width or height specified by the system metric values for cursors or icons, if the cxDesired or cyDesired values are set to zero. If this flag is not specified and cxDesired and cyDesired are set to zero, the function uses the actual resource size. If the resource contains multiple images, the function uses the size of the first image.
LR_LOADFROMFILE 0x00000010	Loads the standalone image from the file specified by name (icon, cursor, or bitmap file).
LR_LOADMAP3DCOLORS 0x00001000	Searches the color table for the image and replaces the following shades of gray with the corresponding 3-D color. Dk Gray, RGB(128,128,128) with COLOR_3DSHADOW Gray, RGB(192,192,192) with COLOR_3DFACE Lt Gray, RGB(223,223,223) with COLOR_3DLIGHT Do not use this option if you are loading a bitmap with a color depth greater than 8bpp.
LR_LOADTRANSPARENT 0x00000020	Retrieves the color value of the first pixel in the image and replaces the corresponding entry in the color table with the default window color (COLOR_WINDOW). All pixels in the image that use that entry become the default window color. This value applies only to images that have corresponding color tables. Do not use this option if you are loading a bitmap with a color depth greater than 8bpp. If fuLoad includes both the LR_LOADTRANSPARENT and LR_LOADMAP3DCOLORS values, LR_LOADTRANSPARENT takes precedence. However, the color table entry is replaced with COLOR_3DFACE rather than COLOR_WINDOW.
LR_MONOCHROME 0x00000001	Loads the image in black and white.
LR_SHARED 0x00008000	Shares the image handle if the image is loaded multiple times. If LR_SHARED is not set, a second call to LoadImage for the same resource will load the image again and return a different handle. When you use this flag, the system will destroy the resource when it is no longer needed. Do not use LR_SHARED for images that have non-standard sizes, that may change after loading, or that are loaded from a file. When loading a system icon or cursor, you must use LR_SHARED or the function will fail to load the resource. This function finds the first image in the cache with the requested resource name, regardless of the size requested.
LR_VGACOLOR 0x00000080	Uses true VGA colors.

Return value

Type: HANDLE

If the function succeeds, the return value is the handle of the newly loaded image.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

If IS_INTRESOURCE(name) is TRUE, then name specifies the integer identifier of the given resource. Otherwise, it is a pointer to a null-terminated string.

If the first character of the string is a pound sign (#), then the remaining characters represent a decimal number that specifies the integer identifier of the resource. For example, the string "#258" represents the identifier 258.

When you are finished using a bitmap, cursor, or icon you loaded without specifying the LR_SHARED flag, you can release its associated memory by calling one of the functions in the following table.

Resource	Release function
Bitmap	DeleteObject
Cursor	DestroyCursor
Icon	DestroyIcon

The system automatically deletes these resources when the process that created them terminates; however, calling the appropriate function saves memory and decreases the size of the process's working set.

Examples

For an example, see Using Window Classes.

Note

The winuser.h header defines LoadImage as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	winuser.h (include Windows.h)
Library	User32.lib
DLL	User32.dll
API set	ext-ms-win-ntuser-gui-l1-1-0 (introduced in Windows 8)

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