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基於JavaScript實現驗證碼功能，javascript驗證碼
本文執行個體為大家分享了Javascript實現驗證碼的具體代碼，供大家參考，具體內容如下
1、一個簡單的例子
建立 test.html
<!DOCTYPE html> <html> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <head> <title>驗證碼</title> <script src = "checkCode.js"> </script> </head> <body> <div> <input type = "text" id = "input"/> <input type = "button" id="code" onclick="createCode()"/> <input type = "button" value = "驗證" onclick = "validate()"/> </div> </body> </html>
建立 checkCode.js
var code ; //在全域定義驗證碼 window.onload = function createCode(){ code = ""; var codeLength = 4;//驗證碼的長度 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');//隨機數 for(var i = 0; i < codeLength; i++) {//迴圈操作 var index = Math.floor(Math.random()*36);//取得隨機數的索引（0~35） code += random[index];//根據索引取得隨機數加到code上 } checkCode.value = code;//把code值賦給驗證碼 } //校正驗證碼 function validate(){ var inputCode = document.getElementById("input").value.toUpperCase(); //取得輸入的驗證碼並轉化為大寫 if(inputCode.length <= 0) { //若輸入的驗證碼長度為0 alert("Empty Code!"); //則彈出請輸入驗證碼 } else if(inputCode != code ) { //若輸入的驗證碼與產生的驗證碼不一致時 alert("Error Code"); //則彈出驗證碼輸入錯誤 createCode();//重新整理驗證碼 document.getElementById("input").value = "";//清空文字框 } else { //輸入正確時 alert("OK"); //彈出^-^ } }
2、點擊的時候不會移動位置的代碼：
<p class="red"><a href="javascript:;" rel="external nofollow" onclick="createCode()">看不清？</a></p>
以上就是本文的全部內容，希望對大家的學習有所協助，也希望大家多多支援幫客之家。
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