getClientRects Method

DHTML文档教程

Retrieves a collection of rectangles that describes the layout of the contents of an object or range within the client. Each rectangle describes a single line.

dhtml语法

collRect = object.getClientRects()

Return Value

Returns the textrectangle collection. each rectangle has four integer properties (top, left, right, and bottom) that each represent a coordinate of the rectangle, in pixels.

Examples

This example uses the getClientRects and getboundingclientrect methods to highlight text lines in an object.

<HEAD>
<SCRIPT>
var rcts;
var keyCount=0;
function Highlight(obj) {
rcts = obj.getClientRects();
rctLength= rcts.length;
if (keyCount > rctLength-1) {
idBeige.style.display="none";
keyCount = 0
}
// set the rendering properties for the yellow DIV
cdRight = rcts[keyCount].right + idBody.scrollLeft;
cdLeft = rcts[keyCount].left + idBody.scrollLeft;
cdTop = rcts[keyCount].top + idBody.scrollTop;
cdBottom = rcts[keyCount].bottom + idBody.scrollTop;
idYellow.style.top = cdTop;
idYellow.style.width = (cdRight-cdLeft) - 5;
idYellow.style.display = 'inline';
// set the rendering properties for the beige DIV
bndRight = obj.getBoundingClientRect().right +
idBody.scrollLeft;
bndLeft = obj.getBoundingClientRect().left +
idBody.scrollLeft;
bndTop = obj.getBoundingClientRect().top +
idBody.scrollTop;
idBeige.style.top = bndTop;
idBeige.style.width = (bndRight-bndLeft) - 5;
idBeige.style.height = cdTop - bndTop;
if (keyCount>0){
idBeige.style.display = 'inline';
}
keyCount++;
}
</SCRIPT>
</HEAD>
<BODY ID="idBody">
<DIV ID="oID_1" onclick="Highlight(this)"
onkeydown="Highlight(this)">
A large block of text should go here. Click this
block of text multiple times to see each line
highlight with every click of the mouse button.
Once each line has been highlighted, the process
begins again starting with the first line.
</DIV>
<DIV STYLE="position:absolute; left:5; top:400;
z-index:-1; background-color:yellow; display:none"
ID="idYellow"></DIV>
<DIV STYLE="position:absolute; left:5; top:400;
z-index:-1; background-color:beige; display:none"
ID="idBeige"></DIV>
</BODY>

This feature requires Microsoft® Internet Explorer 5 or later. Click the following icon to install the latest version. Then reload this page to view the sample.

This example uses the TextRectangle collection with the getClientRects and getBoundingClientRect methods to determine the position of the text rectangle within an element. In each line, the left-justified text does not extend to the right margin of the box that contains the text. Using the collection, you can determine the coordinates of the rectangle that surrounds only the content in each line. The example code reads these rectangle coordinates and instructs the ball to move over the text only, and not to the end of the line.

<HEAD>
<SCRIPT>
var timid = -1;
var timoID_2 = -1;
var nLine;
var nPosInLine;
var oRcts;
var nDivLen;
var nEraser;
function LoadDone() {
oTextRange = document.body.createTextRange();
// Get bounding rect of the range
oRcts = oTextRange.getClientRects();
nLine = 0;
oBndRct = obj.getBoundingClientRect();
nDivLen = oBndRct.right - oBndRct.left + 1;
MoveTo();
}
function MoveTo() {
if (nLine >= oRcts.length) {
nLine = 0;
}
obj.style.top = oRcts[nLine].top;
nPosInLine = oRcts[nLine].left;
nEraser = 0;
timoID_2 = setInterval("MoveToInLine()",60);
}
function MoveToInLine() {
if (nPosInLine >= oRcts[nLine].right - nDivLen) {
clearInterval(timoID_2);
timoID_2 = -1;
obj.style.left = oRcts[nLine].right - nDivLen;
nLine++;
timid = setTimeout("MoveTo()", 100);
return;
}
if (nEraser == 0) {
nEraser = 1;
}
else {
nEraser = 0;
}
im.src = "../common/dot.gif";
obj.style.left = nPosInLine;
nPosInLine += 3;
}
function End() {
if(timid != -1) {
clearInterval(timid);
timid = -1;
}
if(timoID_2 != -1) {
clearInterval(timoID_2);
timoID_2 = -1;
}
}
</SCRIPT>
</HEAD>
<BODY ID="bodyid" onload="LoadDone()"
onresize="End();LoadDone();" onunload="End()">
<P STYLE="text-align:center">
<B>The quick brown fox jumps over the lazy dog.</B>
</P>
<DIV ID="obj" STYLE="position:absolute">
<IMG ID="im" SRC="../common/dot.gif"
BORDER=0 HEIGHT=16 WIDTH=16>
</DIV>
</BODY>

This feature requires Microsoft® Internet Explorer 5 or later. Click the following icon to install the latest version. Then reload this page to view the sample.

是否符合公共标准

There is no public standard that applies to this method.

Applies To

A, ACRONYM, ADDRESS, APPLET, AREA, B, BASE, BASEFONT, BIG, BLOCKQUOTE, BODY, BUTTON, CAPTION, CENTER, CITE, CODE, COL, COLGROUP, COMMENT, CUSTOM, DD, DEL, DFN, DIR, DIV, DL, DT, EM, EMBED, FIELDSET, FONT, FORM, hn, I, IMG, INPUT type=button, INPUT type=checkbox, INPUT type=file, INPUT type=image, INPUT type=password, INPUT type=radio, INPUT type=reset, INPUT type=submit, INPUT type=text, INS, ISINDEX, KBD, LABEL, LEGEND, LI, LINK, LISTING, MAP, MARQUEE, MENU, nextID, NOBR, OBJECT, OL, OPTION, P, PRE, Q, S, SAMP, SELECT, SMALL, SPAN, STRIKE, STRONG, SUB, SUP, TABLE, TBODY, TD, TEXTAREA, TextRange, TFOOT, TH, THEAD, TR, TT, U, UL, VAR, XMP

更多语法参考

TextRectangle