js 是直接写在登录页面的,类似下面这个
var code; //在全局 定义验证码
function createCode() {
code = "";
var codeLength = 6;//验证码的长度
var checkCode = document.getElementById("checkCode");
var selectChar = new Array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9,'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');//所有候选组成验证码的字符,当然也可以用中文的
for (var i = 0; i < codeLength; i++) {
var charIndex = Math.floor(Math.random() * 36);
code += selectChar[charIndex];
}
//alert(code);
if (checkCode) {
checkCode.className = "code";
checkCode.value = code;
}
}
function validate() {
var inputCode = document.getElementById("input1").value;
if (inputCode.length <= 0) {
alert("请输入验证码!");
} else if (inputCode != code) {
alert("验证码输入错误!");
createCode();//刷新验证码
} else {
alert("^-^ OK");
}
}