不区分大小写的 javascript indexOf_js

看看我这个，兼容原来的 indexOf

<script language=JavaScript>
/*
作者:阿牛(牛昆亮) QQ:273352165 MSN:[email protected]

声明:可以免费使用,请您保留此信息
        如果您有什么改过,记得告诉我!
*/
String.prototype._indexOf = String.prototype.indexOf;
String.prototype.indexOf = function()
{
        if(typeof(arguments[arguments.length – 1]) != ‘boolean’)
                return this._indexOf.apply(this,arguments);
        else
        {
                var bi = arguments[arguments.length – 1];
                var thisObj = this;
                var idx = 0;
                if(typeof(arguments[arguments.length – 2]) == ‘number’)
                {
                        idx = arguments[arguments.length – 2];
                        thisObj = this.substr(idx);
                }
               
                var re = new RegExp(arguments[0],bi?’i’:”);
                var r = thisObj.match(re);
                return r==null?-1:r.index + idx;
        }
}

alert(“bcssssasdfsdf”.indexOf(‘A’,3,true));

alert(“bcssssasdfsdf”.indexOf(‘a’,3));
</script>

以下内容为程序代码

<script language=javascript>
/*
作者:阿牛(牛昆亮) QQ:273352165 MSN:[email protected]

声明:可以免费使用,请您保留此信息
        如果您有什么改过,记得告诉我!
*/
String.prototype._indexOf = String.prototype.indexOf;
String.prototype.indexOf = function()
{
        if(typeof(arguments[arguments.length – 1]) != ‘boolean’)
                return this._indexOf.apply(this,arguments);
        else
        {
                var bi = arguments[arguments.length – 1];
                var thisObj = this;
                var idx = 0;
                if(typeof(arguments[arguments.length – 2]) == ‘number’)
                {
                        idx = arguments[arguments.length – 2];
                        thisObj = this.substr(idx);
                }
               
                var re = new RegExp(arguments[0],bi?’i’:”);
                var r = thisObj.match(re);
                return r==null?-1:r.index + idx;
        }
}

alert(“bcssssasdfsdf”.indexOf(‘A’,3,true));

alert(“bcssssasdfsdf”.indexOf(‘a’,3));
</script>