<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>验证码</title>
<style type="text/css">
#code
{
font-family:Arial;
font-style:italic;
font-weight:bold;
border:0;
letter-spacing:2px;
color:blue;
}
</style>
</head>
<body>
<div>
<input type = "text" id = "input"/>
<input type = "button" id="code" onclick="createCode()"/>
<input type = "button" value = "验证" onclick = "validate()"/>
</div>
</body>
</html>
<script>
var code ;
window.onload = function createCode(){
code = "";
var codeLength = 4;
var checkCode = document.getElementById("code");
var random = 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');
for(var i = 0; i < codeLength; i++) {
var index = Math.floor(Math.random()*36);
code += random[index];
}
checkCode.value = code;
}
function validate(){
var inputCode = document.getElementById("input").value.toUpperCase();
if(inputCode.length <= 0) {
alert("请输入验证码！");
}
else if(inputCode != code ) {
alert("验证码输入错误！@_@");
createCode();
document.getElementById("input").value = "";
}
else {
alert("^-^");
}
}
</script>