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).
int DrawText(
|
HDC hDC, |
// handle to device
context |
|
LPCTSTR lpString, |
// pointer to
string to draw |
|
int nCount, |
// string length,
in characters |
|
LPRECT lpRect, |
// pointer to
structure with formatting dimensions |
|
UINT uFormat |
// text-drawing
flags |
|
); |
|
Parameters
hDC
Identifies
the device context.
lpString
Points to the
string to be drawn. If the nCount parameter is -1, the string must be null-terminated.
nCount
Specifies the
number of characters in the string. 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.
lpRect
Points 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. It can be any combination of the following
values:
|
Value |
Description |
|
DT_BOTTOM |
Justifies
the text to the bottom of the rectangle. This value must be combined with
DT_SINGLELINE. |
|
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
or DT_PATH_ELLIPSIS |
Replaces
part of the given string with ellipses, if necessary, so that the result fits
in the specified rectangle. The given
string is not modified unless the DT_MODIFYSTRING flag is specified. You can
specify DT_END_ELLIPSIS to replace characters at the end of the string, or
DT_PATH_ELLIPSIS to replace characters in the middle of the string. If the
string contains backslash (\) characters, DT_PATH_ELLIPSIS preserves as much
as possible of the text after the last backslash. |
|
DT_EXPANDTABS |
Expands tab
characters. The default number of characters per tab is eight. |
|
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_LEFT |
Aligns text
to the left. |
|
DT_MODIFYSTRING |
Modifies
the given string to match the displayed text. This flag has no effect unless
the DT_END_ELLIPSIS or DT_PATH_ELLIPSIS flag is specified. |
|
DT_NOCLIP |
Draws
without clipping. DrawText is somewhat faster when DT_NOCLIP is used. |
|
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. |
|
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 linefeeds 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. |
|
DT_TOP |
Top-justifies
text (single line only). |
|
DT_VCENTER |
Centers
text vertically (single line only). |
|
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-linefeed sequence also breaks the line. |
Note that the
DT_CALCRECT, DT_EXTERNALLEADING, DT_INTERNAL, DT_NOCLIP, and DT_NOPREFIX values
cannot be used with the DT_TABSTOP value.
Return Values
If the
function succeeds, the return value is the height of the text.
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.
See Also