运算验证码
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> </head> <style type="text/css"> .code { font-family: Arial; font-style: italic; color: Red; border: 0; padding: 2px 3px; letter-spacing: 3px; font-weight: bolder; } .unchanged { border: 0; } </style> <script type="text/javascript" src="jquery-1.11.2.min.js"></script> <script language="javascript" type="text/javascript"> var code; //在全局 定义验证码 var code2; //在全局 定义验证码 function createCode() { code = ""; var checkCode = document.getElementById("checkCode"); function RndNum(n) { var rnd = ""; for (var i = 0; i < n; i++) rnd += Math.floor(Math.random() * 10); return rnd; } var num = RndNum(2); var num2 = RndNum(2); code = num + "+" + num2 + "="; code2 = parseInt(num) + parseInt(num2) if (checkCode) { checkCode.className = "code"; checkCode.value = code; } } </script> <body onload="createCode() "> <form action="#"> <input type="text" id="input1" /> <input type="text" onclick="createCode()" readonly="readonly" id="checkCode" class="unchanged" style="width: 80px;background-color: gainsboro;"/><br /> <input type="submit" value="验证" id="validate"/> </form> </body> </html> <script type="text/javascript"> $(document).ready(function () { $("#validate").click(function () { var inputCode = document.getElementById("input1").value; if (inputCode.length <= 0) { alert("请输入验证码!"); } else if (inputCode != code2) { alert("验证码输入错误!"); createCode(); //刷新验证码 } else { alert("验证码输入正确!"); } }); }) </script>