在光标处插入字符串的实现代码 兼容IE,Firefox

代码如下:
// 在光标处插入字符串
// myField 文本框对象
// 要插入的值
function insertAtCursor(myField, myValue)
{
//IE support
if (document.selection)
{
myField.focus();
sel = document.selection.createRange();
sel.text = myValue;
sel.select();
}
//MOZILLA/NETSCAPE support
else if (myField.selectionStart || myField.selectionStart == '0')
{
var startPos = myField.selectionStart;
var endPos = myField.selectionEnd;
// save scrollTop before insert
var restoreTop = myField.scrollTop;
myField.value = myField.value.substring(0, startPos) + myValue + myField.value.substring(endPos,myField.value.length);
if (restoreTop > 0)
{
// restore previous scrollTop
myField.scrollTop = restoreTop;
}
myField.focus();
myField.selectionStart = startPos + myValue.length;
myField.selectionEnd = startPos + myValue.length;
} else {
myField.value += myValue;
myField.focus();
}
}

下面是脚本之家演示代码：
<script> // 在光标处插入字符串 // myField 文本框对象 // 要插入的值 function insertAtCursor(myField, myValue) { //IE support if (document.selection) { myField.focus(); sel = document.selection.createRange(); sel.text = myValue; sel.select(); } //MOZILLA/NETSCAPE support else if (myField.selectionStart || myField.selectionStart == '0') { var startPos = myField.selectionStart; var endPos = myField.selectionEnd; // save scrollTop before insert var restoreTop = myField.scrollTop; myField.value = myField.value.substring(0, startPos) + myValue + myField.value.substring(endPos,myField.value.length); if (restoreTop > 0) { // restore previous scrollTop myField.scrollTop = restoreTop; } myField.focus(); myField.selectionStart = startPos + myValue.length; myField.selectionEnd = startPos + myValue.length; } else { myField.value += myValue; myField.focus(); } } </script> <form> <textarea id=demo style="width:500px; height:300px">将鼠标定位到这里的任意位置，然后点击下面的按钮，即可测试效果</textarea> <input type=button onclick=insertAtCursor(document.getElementById('demo'),"脚本之家") value=脚本之家 ID=Button1> <input type=button onclick=insertAtCursor(document.getElementById('demo'),"jb51.net") value=jb51.net ID=Button2> </form>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]