=IE支持document.selection

=Firefox，Chrome,Safari以及Opera都有selectionStart和selectionEnd属性

复制代码 代码如下:

function insertText(obj,str) {

if (document.selection) {

var sel = document.selection.createRange();

sel.text = str;

} else if (typeof obj.selectionStart === 'number' && typeof obj.selectionEnd === 'number') {

var startPos = obj.selectionStart,

endPos = obj.selectionEnd,

cursorPos = startPos,

tmpStr = obj.value;

obj.value = tmpStr.substring(0, startPos) + str + tmpStr.substring(endPos, tmpStr.length);

cursorPos += str.length;

obj.selectionStart = obj.selectionEnd = cursorPos;

} else {

obj.value += str;

}

}

function moveEnd(obj){

obj.focus();

var len = obj.value.length;

if (document.selection) {

var sel = obj.createTextRange();

sel.moveStart('character',len);

sel.collapse();

sel.select();

} else if (typeof obj.selectionStart == 'number' && typeof obj.selectionEnd == 'number') {

obj.selectionStart = obj.selectionEnd = len;

}

}

复制代码 代码如下:

<input type="button" value="插入文字"></input>

复制代码 代码如下:

<input type="button" value="移到末尾"></input>