怎么用JavaScript记录光标在编辑器中的位置
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具体代码如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<script type="text/javascript">
function $(ele){return document.getElementById(ele)}
//记录编辑器中的位置
var selection_start;
var selection_end;
function savePos(textBox){
var start=0;
var end=0;
if(typeof(textBox.selectionStart) == "number"){ // not ie
//alert(typeof(textBox.selectionStart) );
start = textBox.selectionStart;
end = textBox.selectionEnd;
}
else if(document.selection){
var range = document.selection.createRange();
if(range.parentElement().id == textBox.id){
var range_all = document.body.createTextRange();
range_all.moveToElementText(textBox);
for (start=0; range_all.compareEndPoints("StartToStart", range) < 0; start++)
range_all.moveStart('character', 1);
for (var i = 0; i <= start; i ++){
if (textBox.value.charAt(i) == '/n')
start++;
}
var range_all = document.body.createTextRange();
range_all.moveToElementText(textBox);
for (end = 0; range_all.compareEndPoints('StartToEnd', range) < 0; end ++)
range_all.moveStart('character', 1);
for (var i = 0; i <= end; i ++){
if (textBox.value.charAt(i) == '/n')
end ++;
}
}
}
selection_start = start;
selection_end = end;
}
</script>
<form action="" id="test">
<textarea id="t" onfocus="savePos(this);$('log').value=selection_start" onkeydown="savePos(this);$('log').value=selection_start" onmousedown="savePos(this);$('log').value=selection_start" onmouseup="savePos(this);$('log').value=selection_start" >
</textarea>
<input type="text" id="log" />
</form>
</body>
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