本篇文章主要是對javascript實現數字驗證碼的簡單實例進行了介紹,需要的朋友可以過來參考下,希望對大家有所幫助
實例如下: 代碼如下: <!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> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>JS驗證碼</title> <style type="text/css"> .code { background-image:url(code.jpg); font-family:Arial; font-style:italic; color:Red; border:0; padding:2px 3px; letter-spacing:3px; font-weight:bolder; } .unchanged { border:0; } </style> <script language="javascript" type="text/javascript"> var code ; //在全局 定義驗證碼 function createCode() { code = ""; var codeLength = 4;//驗證碼的長度 var checkCode = document.getElementById("checkCode"); var selectChar = new Array(0,1,2,3,4,5,6,7,8,9);//所有候選組成驗證碼的字符,當然也可以用中文的 for(var i=0;i<codeLength;i++) { var charIndex = Math.floor(Math.random()*10); 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("請輸入驗證碼!"); } else if(inputCode != code ) { alert("驗證碼輸入錯誤!"); createCode();//刷新驗證碼 } else { alert("OK"); } } </script> </head> <body onload="createCode()"> <form action="#"> <input type="text" id="input1" /> <input type="text" onclick="createCode()" readonly="readonly" id="checkCode" class="unchanged" style="width: 80px" /><br /> <input id="Button1" onclick="validate();" type="button" value="確定" /> </form> </body> </html>