//去除空格
String.prototype.Trim = function()    
{    
	return this.replace(/(^\s*)|(\s*$)/g, "");    
}

“测试     ”.Trim();

?

数组去重
var arr=["a","b","c","a","ba","bc"];
alert(arr.join(",").match( /([^,]+)(?!.*,\1(,|$))/ig));

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