如何在textarea的光标位置插入文字

在网上看了很多用js在光标处插入文字的代码，很多都没有用，互抄而已，浪费时间。最近用到一个新方法，可以到达这个需求。IE支持document.selection，Firefox，Chrome,Safari以及Opera都有selectionStart和selectionEnd属性。

效果演示

//在光标位置插入文字
function insertText(obj,str) {
obj.focus();
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;
}
}

欢迎访问www.nowamagic.net






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;
    }
}