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ExtTextOut
The ExtTextOut function draws text using the currently selected font, background color, and text color. You can optionally provide dimensions to be used for clipping, opaquing, or both.
BOOL ExtTextOut(
HDC hdc, // handle to DC
int X, // x-coordinate of reference point
int Y, // y-coordinate of reference point
UINT fuOptions, // text-output options
CONST RECT* lprc, // optional dimensions
LPCTSTR lpString, // string
UINT cbCount, // number of characters in string
CONST INT* lpDx // array of spacing values
);
Parameters
- hdc
[in] Handle to the device context.
X
[in] Specifies the logical x-coordinate of the reference point used to position the string.
Y
[in] Specifies the logical y-coordinate of the reference point used to position the string.
fuOptions
[in] Specifies how to use the application-defined rectangle. This parameter can be one or more of the following values. Value Meaning
ETO_CLIPPED The text will be clipped to the rectangle.
ETO_GLYPH_INDEX The lpString array refers to an array returned from GetCharacterPlacement and should be parsed directly by GDI as no further language-specific processing is required. Glyph indexing only applies to TrueType fonts, but the flag can be used for bitmap and vector fonts to indicate that no further language processing is necessary and GDI should process the string directly. Note that all glyph indexes are 16-bit values even though the string is assumed to be an array of 8-bit values for raster fonts.
For ExtTextOutW, the glyph indexes are saved to a metafile. However, to display the correct characters the metafile must be played back using the same font. For ExtTextOutA, the glyph indexes are not saved.
ETO_NUMERICSLATIN To display numbers, use European digits.
ETO_NUMERICSLOCAL To display numbers, use digits appropriate to the locale.
ETO_OPAQUE The current background color should be used to fill the rectangle.
ETO_PDY When this is set, the array pointed to by lpDx contains pairs of values. The first value of each pair is, as usual, the distance between origins of adjacent character cells, but the second value is the displacement along the vertical direction of the font.
ETO_RTLREADING Middle-Eastern Windows: If this value is specified and a Hebrew or Arabic font is selected into the device context, the string is output using right-to-left reading order. If this value is not specified, the string is output in left-to-right order. The same effect can be achieved by setting the TA_RTLREADING value in SetTextAlign. This value is preserved for backward compatability.
The ETO_GLYPH_INDEX and ETO_RTLREADING values cannot be used together. Because ETO_GLYPH_INDEX implies that all language processing has been completed, the function ignores the ETO_RTLREADING flag if also specified.
lprc
[in] Pointer to an optional RECT structure that specifies the dimensions of a rectangle that is used for clipping, opaquing, or both.
lpString
[in] Pointer to a string that specifies the text to be drawn. The string does not need to be zero-terminated, since cbCount specifies the length of the string.
cbCount
[in] Specifies the length of the string. For the ANSI function it is a BYTE count and for the Unicode function it is a WORD count. Note that for the ANSI function, characters in SBCS code pages take one byte each, while most characters in DBCS code pages take two bytes; for the Unicode function, most currently defined Unicode characters (those in the Basic Multilingual Plane (BMP)) are one WORD while Unicode surrogates are two WORDs.
Windows 95/98/Me: This value may not exceed 8192.
lpDx
[in] Pointer to an optional array of values that indicate the distance between origins of adjacent character cells. For example, lpDx[i] logical units separate the origins of character cell i and character cell i + 1.
Return Values
If the string is drawn, the return value is nonzero. However, if the ANSI version of ExtTextOut is called with ETO_GLYPH_INDEX, the function returns TRUE even though the function does nothing.
If the function fails, the return value is zero.
Windows NT/2000 or later: To get extended error information, call GetLastError.
Remarks
Although not true in general, Windows 95/98 supports the Unicode version of this function as well as the ANSI version.
The current text-alignment settings for the specified device context determine how the reference point is used to position the text. The text-alignment settings are retrieved by calling the GetTextAlign function. The text-alignment settings are altered by calling the SetTextAlign function.
If the lpDx parameter is NULL, the ExtTextOut function uses the default spacing between characters. The character-cell origins and the contents of the array pointed to by the lpDx parameter are specified in logical units. A character-cell origin is defined as the upper-left corner of the character cell.
By default, the current position is not used or updated by this function. However, an application can call the SetTextAlign function with the fMode parameter set to TA_UPDATECP to permit the system to use and update the current position each time the application calls ExtTextOut for a specified device context. When this flag is set, the system ignores the X and Y parameters on subsequent ExtTextOut calls.
For the ANSI version of ExtTextOut, the lpDx array has the same number of INT values as there are bytes in lpString. For DBCS characters, you can apportion the dx in the lpDx entries between the lead byte and the trail byte, as long as the sum of the two bytes adds up to the desired dx. For DBCS characters with the Unicode version of ExtTextOut, each Unicode glyph gets a single pdx entry.
Note, the alpDx values from GetTextExtentExPoint are not the same as the lpDx values for ExtTextOut. To use the alpDx values in lpDx, you must first process them.
Requirements
- Windows NT/2000 or later: Requires Windows NT 3.1 or later.
- Windows 95/98/Me: Requires Windows 95 or later.
- Header: Declared in Wingdi.h; include Windows.h.
- Library: Use Gdi32.lib.
- Unicode: Implemented as Unicode and ANSI versions on all platforms.
See Also
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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time