Javascript驗證Visa和MasterCard信用卡號
來源：互聯網
上載者：User
//visa<HTML> <head> <title>Visa Example</title> <script type="text/javascript"> function luhnCheckSum(sCardNum) { var iOddSum = 0; var iEvenSum = 0; var bIsOdd = true; for (var i=sCardNum.length-1; i >= 0; i--) { var iNum = parseInt(sCardNum.charAt(i)); if (bIsOdd) { iOddSum += iNum; } else { iNum = iNum * 2; if (iNum > 9) { iNum = eval(iNum.toString().split("").join("+")); } iEvenSum += iNum; } bIsOdd = !bIsOdd; } return ((iEvenSum + iOddSum) % 10 == 0); } function isValidVisa(sText) { var reVisa = /^(4\d{12}(?:\d{3})?)$/; if (reVisa.test(sText)) { return luhnCheckSum(RegExp.$1); } else { return false; } } function validate() { var oInput1 = document.getElementById("txt1"); if (isValidVisa(oInput1.value)) { alert("Valid"); } else { alert("Invalid!"); } } </script> </head> <body> <P>Visa Number: <input type="text" id="txt1" /><br /> <input type="button" value="Validate" onclick="validate()" /></p> </body></html>//MasterCardview sourceprint?<html> <head> <title>MasterCard Example</title> <script type="text/javascript"> function luhnCheckSum(sCardNum) { var iOddSum = 0; var iEvenSum = 0; var bIsOdd = true; for (var i=sCardNum.length-1; i >= 0; i--) { var iNum = parseInt(sCardNum.charAt(i)); if (bIsOdd) { iOddSum += iNum; } else { iNum = iNum * 2; if (iNum > 9) { iNum = eval(iNum.toString().split("").join("+")); } iEvenSum += iNum; } bIsOdd = !bIsOdd; } return ((iEvenSum + iOddSum) % 10 == 0); } function isValidMasterCard(sText) { var reMasterCard = /^(5[1-5]\d{2})[\s\-]?(\d{4})[\s\-]?(\d{4})[\s\-]?(\d{4})$/; if (reMasterCard.test(sText)) { var sCardNum = RegExp.$1 + RegExp.$2 + RegExp.$3 + RegExp.$4; return luhnCheckSum(sCardNum); } else { return false; } } function validate() { var oInput1 = document.getElementById("txt1"); if (isValidMasterCard(oInput1.value)) { alert("Valid"); } else { alert("Invalid!"); } } </script> </head> <body> <P>MasterCard Number: <input type="text" id="txt1" /><br /> <input type="button" value="Validate" onclick="validate()" /></p> </body></html>
