JS實現10進制和26進制的轉換

轉載：https://blog.csdn.net/quentain/article/details/52803891

 

//將26進制轉10進制
 var ConvertNum = function (str) {
 var n = 0;
 var s = str.match(/./g);//求出字符數組
 var j = 0;
 for (var i = str.length - 1, j = 1; i >= 0; i--, j *= 26) {
 var c = s[i].toUpperCase();
 if (c < 'A' || c > 'Z') {
 return 0;
 }
 n += (c.charCodeAt(0) - 64) * j;
 }
 return n;
 }
 //測試
 var teststr = "AB";
 alert(ConvertNum(teststr));
 //將10進制轉26進制
 var Convert26=function(num){
 var str="";
 while (num > 0){
 var m = num % 26;
 if (m == 0){
 m = 26;
 }
 str = String.fromCharCode(m + 64) + str;
 num = (num - m) / 26;
 }
 return str;
 }
  
 //測試
 var num = 28;
 alert(Convert26(num));