function checkPwd() { var pwd = document.getElementById("txtPwd1").value; //密码框的值 var len = pwd.length; //密码的长度 var rank = 0; //密码强度 if (len < 6 || len > 20) { var s = "密码长度应为6至20个字符"; document.getElementById("pwdmsg").innerHTML = s.fontcolor("red"); document.getElementById("txtPwd1").focus(); return; } else { for (var i = 0; i < len; i++) { var c = pwd.charCodeAt(i); if (c > 48 && c < 57) { //有数字 rank = 1; } else if ((c > 65 && c < 90) || (c > 97 && c < 122)) { //有字母 if (rank == 1) { rank = 2; } } else if ((c > 90 && c < 97) || (c > 57 && c < 65) || (c < 48) || (c > 122)) { //有其他 rank = 3; } } switch (rank) { case 1: var s = "密码强度为:弱"; document.getElementById("pwdmsg").innerHTML = s.fontcolor("green"); break; case 2: var s = "密码强度为:中"; document.getElementById("pwdmsg").innerHTML = s.fontcolor("green"); break; case 3: var s = "密码强度为:强"; document.getElementById("pwdmsg").innerHTML = s.fontcolor("green"); break; default: } } }
判断密码是否包含啥,用ASC II码判断