var = ["弱","中","强","超强"];
    function checkStrong(val) {
                var modes = 0;
                if (val.length < 6) return 0;
                if (/\d/.test(val)) modes++; //数字
                if (/[a-z]/.test(val)) modes++; //小写
                if (/[A-Z]/.test(val)) modes++; //大写  
                if (/\W/.test(val)) modes++; //特殊字符
                if (val.length > 12) return 4;
                return modes;
            }