Bank card algorithm Rules

/** *luhn Calibration Algorithm verifies bank card number *description: Bank card number luhm check *luhm check rule: 16-digit bank card number (19-bit generic): * *. 15 (or 18) bit cards with no check digit numbered 1 to 15 (18) from right    , the number on the odd digit number is multiplied by 2.    * *. Add all 10 bits of the singularity product, plus the numbers on all even digits.    The addition and calibration potentials are divisible by 10. * Method steps are clear, easy to understand, need to refer to the page Jquery.js *bankno for the bank card number */function Luhmcheck (bankno) {var lastnum = bankno.substr (ba Nkno.length-1, 1);//Take Out the last one (compared to luhm) var first15num = bankno.substr (0, bankno.length-1);//First 15 or 18-bit var n        Ewarr = new Array ();        for (var i = first15num.length-1; i >-1; i--) {///First 15 or 18-bit reverse-deposit into array newarr.push (FIRST15NUM.SUBSTR (i, 1));  } var Arrjishu = new Array (); The product <9 var arrJiShu2 = new Array () of odd digits * *;  The product >9 var Arroushu = new Array () of odd digits * *; An even-bit array for (var j = 0; J < Newarr.length; J + +) {if ((j + 1)% 2 = = 1) {//odd digit if (par                Seint (Newarr[j]) * 2 < 9) Arrjishu.push (parseint (Newarr[j]) * 2); else ARRJISHU2.PUsh (parseint (Newarr[j]) * 2);        } else//even digit Arroushu.push (newarr[j]); } var jishu_child1 = new Array ();//Odd digit * * >9 after the partition of the array single-digit var jishu_child2 = new Array ();//Odd Digit * * &GT;9 Division            After the array of 10-digit for (var h = 0; h < arrjishu2.length; h++) {Jishu_child1.push (parseint (arrjishu2[h])% 10);        Jishu_child2.push (parseint (arrjishu2[h])/10); } var Sumjishu = 0; The sum of the array of odd digits * < 9 is var Sumoushu = 0; The sum var of an even-bit array is sumJiShuChild1 = 0; Odd Digit * * >9 after the partition of the array of single-digit and var sumJiShuChild2 = 0;        Odd Digit * * >9 after the partition of the array of 10-digit and var sumtotal = 0;        for (var m = 0; m < arrjishu.length; m++) {Sumjishu = Sumjishu + parseint (arrjishu[m]);        } for (var n = 0; n < arroushu.length; n++) {Sumoushu = Sumoushu + parseint (Arroushu[n]); } for (var p = 0; p < jishu_child1.length; p++) {sumJiShuChild1 = SumJiShuChild1 + parseint (jISHU_CHILD1[P]);        SumJiShuChild2 = sumJiShuChild2 + parseint (jishu_child2[p]); }//Calculate sum SumTotal = parseint (Sumjishu) + parseint (Sumoushu) + parseint (sumJiShuChild1) + parseint (Sumjishuch        ILD2); Calculate Luhm value var k = parseint (sumtotal)% 10 = = 0?        10:parseint (sumtotal)% 10;        var luhm = 10-k;        var my = false;        if (Lastnum = = luhm) {//luhm verified through my = true;        } else {//bank card number must conform to LUHM check my = false;    } return my; }

　　

Bank card algorithm Rules