我需要计算多次出现两个字符之间的字符数

Question

我需要计算＆lt;＆gt;之间文本的长度在长输入字符串中，＆lt;＆gt;将由用户多次重复。

   var Msg1 = "The lengh of <this> has to be calculated. And also <of this>. And of <this>";
   var regex = /<([^>]*)>/g;
   var IntExam = regex.exec(Msg1);
   var IntExL = IntExam[1].length;
   alert(IntExL);

但是，当我想获得＆lt;＆gt;所包含的所有文字的长度时，我只会得到错误的长度。

Answer 1

使用循环：

var Msg1 = "The lengh of <this> has to be calculated. And also <of this>. And of <this>";
var regex = /<([^>]*)>/g;
var totalLength = 0;
do {
  var IntExam = regex.exec(Msg1);
  if(!IntExam) break;
  var IntExL = IntExam[1].length;
  totalLength += IntExL;
} while (IntExam);
alert(totalLength);

或简洁版（源自JaromandaX的评论）：

var Msg1 = "The lengh of <this> has to be calculated. And also <of this>. And of <this>";
var regex = /<([^>]*)>/g;
var totalLength = Msg1.match(regex).map(v => v.length-2).reduce((a, b) => a + b);
alert(totalLength);