Javascript while循环条件不起作用

Question

我有一个对象团队和一个字符串sharelink

var teams = {
  team1 : {
    roster : []
  },
  team2 : {
    roster : []
  },
};
var sharelink = "localhost:5000/team1=9234&5678&9999&6585team2=15566";

我想通过分享链解析每个团队的子串由＆＃34; t＆＃34;并使用以下代码使用它：

for(var team in teams){
  var start = sharelink.search(team) + team.length + 1;
  var end = start + 1;
  while(sharelink[end]){
    if(sharelink[end] == "t"){
      break;
    }
    end++;
  }
  console.log(sharelink.slice(start, end));
  /*
  returns "9234&5678&9999&6585" on the first iteration and
  "15566" on the second and final time through just like I want it to  
  */
}

当我只是为了获得team1＆＃39; s substring

而只是使用while循环时，它也可以正常工作

var start = sharelink.search("team1") + "team1".length + 1;
  var end = start + 1;
  while(sharelink[end] != "t"){
    end++;
  }
console.log(sharelink.slice(start, end));
//returns "9234&5678&9999&6585" just as intended

但是下面的代码进入了无限循环。

for(var team in teams){
  var start = sharelink.search(team) + team.length + 1;
  var end = start + 1;
  while(sharelink[end] != "t"){
    end++;
  }
}

为什么？