// 随机验证码
var randomStr,randomCode = new Array
var randomNum, // 设置倾斜度数
    minNum = -20, // 最低-20
    maxNum = 20; // 最大20
function randomCoding(){
    //创建26个字母数组
    var arr = ['A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']; // 添加数字复制后面,'0','1','2','3','4','5','6','7','8','9'
    var idvalue ='';
    var n = 4;//这个值可以改变的，对应的生成多少个字母，根据自己需求所改
    for(var i=0;i<n;i++){
        idvalue+=arr[Math.floor(Math.random()*26)];// 添加数字需改成 36
    }
    randomStr = idvalue
    randomCode = idvalue.split('') // 转数组
    return idvalue;
}