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 DrawText

The DrawText function draws formatted text in the specified rectangle. It formats the text according to the specified method (expanding tabs, justifying characters, breaking lines, and so forth).

To specify additional formatting options, use the DrawTextEx function.

int DrawText(
  HDC       hDC,        // handle to DC
  LPCTSTR   lpString,   // text to draw
  int       nCount,     // text length
  LPRECT    lpRect,     // formatting dimensions
  UINT      uFormat     // text-drawing options
);

Parameters

hDC
Handle to the device context.
lpString
Pointer to the string that specifies the text to be drawn. If the nCount parameter is –1, the string must be null-terminated. If uFormat includes DT_MODIFYSTRING, the function could add up to four additional characters to this string. The buffer containing the string should be large enough to accommodate these extra characters.
nCount
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. If nCount is –1, then the lpString parameter is assumed to be a pointer to a null-terminated string and DrawText computes the character count automatically. Windows 95/98/Me: This number many not exceed 8192.
lpRect
Pointer to a RECT structure that contains the rectangle (in logical coordinates) in which the text is to be formatted.
uFormat
Specifies the method of formatting the text. This parameter can be one or more of the following values. Value Description DT_BOTTOM Justifies the text to the bottom of the rectangle. This value is used only with the DT_SINGLELINE value. DT_CALCRECT Determines the width and height of the rectangle. If there are multiple lines of text, DrawText uses the width of the rectangle pointed to by the lpRect parameter and extends the base of the rectangle to bound the last line of text. If there is only one line of text, DrawText modifies the right side of the rectangle so that it bounds the last character in the line. In either case, DrawText returns the height of the formatted text but does not draw the text. DT_CENTER Centers text horizontally in the rectangle. DT_EDITCONTROL Duplicates the text-displaying characteristics of a multiline edit control. Specifically, the average character width is calculated in the same manner as for an edit control, and the function does not display a partially visible last line. DT_END_ELLIPSIS For displayed text, if the end of a string does not fit in the rectangle, it is truncated and ellipses are added. If a word that is not at the end of the string goes beyond the limits of the rectangle, it is truncated without ellipses. The string is not modified unless the DT_MODIFYSTRING flag is specified. Compare with DT_PATH_ELLIPSIS and DT_WORD_ELLIPSIS. DT_EXPANDTABS Expands tab characters. The default number of characters per tab is eight. The DT_WORD_ELLIPSIS, DT_PATH_ELLIPSIS, and DT_END_ELLIPSIS values cannot be used with the DT_EXPANDTABS value. DT_EXTERNALLEADING Includes the font external leading in line height. Normally, external leading is not included in the height of a line of text. DT_HIDEPREFIX Windows 2000 or later: Ignores the ampersand (&) prefix character in the text. The letter that follows will not be underlined, but other mnemonic-prefix characters are still processed. For example:
input string: "A&bc&&d" normal: "Abc&d" DT_HIDEPREFIX: "Abc&d"
Compare with DT_NOPREFIX and DT_PREFIXONLY. DT_INTERNAL Uses the system font to calculate text metrics. DT_LEFT Aligns text to the left. DT_MODIFYSTRING Modifies the specified string to match the displayed text. This value has no effect unless DT_END_ELLIPSIS or DT_PATH_ELLIPSIS is specified. DT_NOCLIP Draws without clipping. DrawText is somewhat faster when DT_NOCLIP is used. DT_NOFULLWIDTHCHARBREAK Windows 98/Me, Windows 2000 or later: Prevents a line break at a DBCS (double-wide character string), so that the line breaking rule is equivalent to SBCS strings. For example, this can be used in Korean windows, for more readability of icon labels. This value has no effect unless DT_WORDBREAK is specified. DT_NOPREFIX Turns off processing of prefix characters. Normally, DrawText interprets the mnemonic-prefix character & as a directive to underscore the character that follows, and the mnemonic-prefix characters && as a directive to print a single &. By specifying DT_NOPREFIX, this processing is turned off. For example,
input string: "A&bc&&d" normal: "Abc&d" DT_NOPREFIX: "A&bc&&d"
Compare with DT_HIDEPREFIX and DT_PREFIXONLY. DT_PATH_ELLIPSIS For displayed text, replaces characters in the middle of the string with ellipses so that the result fits in the specified rectangle. If the string contains backslash (\) characters, DT_PATH_ELLIPSIS preserves as much as possible of the text after the last backslash. The string is not modified unless the DT_MODIFYSTRING flag is specified.

Compare with DT_END_ELLIPSIS and DT_WORD_ELLIPSIS.

DT_PREFIXONLY Windows 2000 or later: Draws only an underline at the position of the character following the ampersand (&) prefix character. Does not draw any other characters in the string. For example,
input string: "A&bc&&d" normal: "Abc&d" DT_PREFIXONLY: " _ "
Compare with DT_HIDEPREFIX and DT_NOPREFIX. DT_RIGHT Aligns text to the right. DT_RTLREADING Layout in right-to-left reading order for bi-directional text when the font selected into the hdc is a Hebrew or Arabic font. The default reading order for all text is left-to-right. DT_SINGLELINE Displays text on a single line only. Carriage returns and line feeds do not break the line. DT_TABSTOP Sets tab stops. Bits 15–8 (high-order byte of the low-order word) of the uFormat parameter specify the number of characters for each tab. The default number of characters per tab is eight.The DT_CALCRECT, DT_EXTERNALLEADING, DT_INTERNAL, DT_NOCLIP, and DT_NOPREFIX values cannot be used with the DT_TABSTOP value. DT_TOP Justifies the text to the top of the rectangle. DT_VCENTER Centers text vertically. This value is used only with the DT_SINGLELINE value. DT_WORDBREAK Breaks words. Lines are automatically broken between words if a word would extend past the edge of the rectangle specified by the lpRect parameter. A carriage return-line feed sequence also breaks the line. DT_WORD_ELLIPSIS Truncates any word that does not fit in the rectangle and adds ellipses. Compare with DT_END_ELLIPSIS and DT_PATH_ELLIPSIS.

Return Values If the function succeeds, the return value is the height of the text in logical units. If DT_VCENTER or DT_BOTTOM is specified, the return value is the offset from lpRect->top to the bottom of the drawn text

If the function fails, the return value is zero.

Windows NT/2000 or later: To get extended error information, call GetLastError.

Remarks

The DrawText function uses the device context's selected font, text color, and background color to draw the text. Unless the DT_NOCLIP format is used, DrawText clips the text so that it does not appear outside the specified rectangle. All formatting is assumed to have multiple lines unless the DT_SINGLELINE format is specified. If the selected font is too large for the specified rectangle, the DrawText function does not attempt to substitute a smaller font. The DrawText function supports only fonts whose escapement and orientation are both zero. The text alignment mode for the device context must include the TA_LEFT, TA_TOP, and TA_NOUPDATECP flags. For an example, see Displaying Keyboard Input.

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 Winuser.h; include Windows.h.
• Library: Use User32.lib.
• Unicode: Implemented as Unicode and ANSI versions on Windows NT/2000.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time