JavaScript 验证码的实例代码(附效果图)

蔚落 2022-09-26 01:49 161阅读 0赞

<html xmlns="http://www.w3.org/1999/xhtml">
    <head runat="server">
        <title></title>
        <style type="text/css">
        .code
        {
                background:url(code_bg.jpg);
                font-family:Arial;
                font-style:italic;
                 color:blue;
                 font-size:30px;
                 border:0;
                 padding:2px 3px;
                 letter-spacing:3px;
                 font-weight:bolder;             
                 float:left;            
                 cursor:pointer;
                 width:150px;
                 height:60px;
                 line-height:60px;
                 text-align:center;
                 vertical-align:middle;
    
        }
        a
        {
            text-decoration:none;
            font-size:12px;
            color:#288bc4;
            }
        a:hover
        {
           text-decoration:underline;
            }
        </style>
        <script language="javascript" type="text/javascript">
    
            var code;
            function createCode() {
                code = "";
                var codeLength = 6; //验证码的长度
                var checkCode = document.getElementById("checkCode");
                var codeChars = 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',
                '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 charNum = Math.floor(Math.random() * 52);
                    code += codeChars[charNum];
                }
                if (checkCode) 
                {
                    checkCode.className = "code";
                    checkCode.innerHTML = code;
                }
            }
            function validateCode() 
            {
                var inputCode = document.getElementById("inputCode").value;
                if (inputCode.length <= 0) 
                {
                    alert("请输入验证码！");
                }
                else if (inputCode.toUpperCase() != code.toUpperCase()) 
                {
                    alert("验证码输入有误！");
                    createCode();
                }
                else 
                {
                    alert("验证码正确！");
                }        
            }    
         </script>
    
    </head>
    <body οnlοad="createCode()">
        <form id="form1" runat="server" οnsubmit="validateCode()">
        <div>
        <table border="0" cellspacing="5" cellpadding="5" >
            <tr>
                <td></td><td> <div class="code" id="checkCode" οnclick="createCode()" ></div></td>
                <td><a  href="#" οnclick="createCode()">看不清换一张</a></td>
            </tr>
            <tr>
                <td>验证码：</td><td><input  style="float:left;" type="text"   id="inputCode" /></td><td>请输入验证码</td>
            </tr>
            <tr><td></td><td><input id="Button1"  οnclick="validateCode();" type="button" value="确定" /></td><td></td>
            </tr>
        </table>
        </div>
        </form>
    </body>
    </html>