JS获取指定长度的随机码

/**
 * 获取指定长度的随机码
 * @param codeLength
 * @return {String}
 */
function createCode(codeLength)
{
    var code = "";
    var selectChar=new Array(0,1,2,3,4,5,6,7,8,9,"A","B","C","D","E","F","G","H","I","G","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z");
    for(var i=0; i<codeLength; i++)
    {
        var charIndex=Math.floor(Math.random()*32);
        code+=selectChar[charIndex];
    }
    if(code.length!=codeLength)
    {
        createCode();
    }
    return code;
}