Question

我正在尝试在数组中插入一个值，但是当我尝试插入值时，它给了我未定义的Connot set Property'0'。但显然我已经定义了数组。

错误行：

this.enemyMinions[i] = new EnemyCombatMinion(new Minion(enemyMinionInfo[0], 0, enemyMinionInfo[1], enemyMinionInfo[2], enemyMinionInfo[3], 0, 0, 0, 0, 0, 0));

这就是整个代码：

function Combat() {
  this.enemyMinions = [];
  this.playerMinions = [];
  this.currentEnemyMinion = null;
  this.currentPlayerMinion = null;
}

Combat.prototype.initialize = function() {
  var o = 0;
  for(var i = 0; i < partySlots.length; i++) {
    if(partySlots[i]) {
      this.playerMinions[o] = PlayerCombatMinion(partySlots[i]);
      o++;
    }
  }
  this.currentPlayerMinion = this.playerMinions[0];

   $.ajax({
      url: "./api/generateEnemyCombatMinions.php",
      cache: false
    })
    .done(function( html ) {          
      var response = html.split(":::");
      for(var i = 0; i < response.length; i++) {
        var enemyMinionInfo = response[i].split("::");
        this.enemyMinions[i] = new EnemyCombatMinion(new Minion(enemyMinionInfo[0], 0, enemyMinionInfo[1], enemyMinionInfo[2], enemyMinionInfo[3], 0, 0, 0, 0, 0, 0));
      }
      alert(this.enemyMinions.length);
    });   

}

如您所见，我在类构造函数中将this.enemyMinons声明为文字，并尝试在initialize方法中为其定义一个值。

Answer 1

done()回调不会将您的Combat对象用作this。保存指向initialize()函数中对象的指针，以便稍后可以访问该对象。

Combat.prototype.initialize = function() {
  var o = 0;
  for(var i = 0; i < partySlots.length; i++) {
    if(partySlots[i]) {
      this.playerMinions[o] = PlayerCombatMinion(partySlots[i]);
      o++;
    }
  }
  this.currentPlayerMinion = this.playerMinions[0];

  // this is new
  var that= this;

   $.ajax({
      url: "./api/generateEnemyCombatMinions.php",
      cache: false
    })
    .done(function( html ) {          
      var response = html.split(":::");
      for(var i = 0; i < response.length; i++) {
        var enemyMinionInfo = response[i].split("::");
        // use "that" here instead of "this"
        that.enemyMinions[i] = new EnemyCombatMinion(new Minion(enemyMinionInfo[0], 0, enemyMinionInfo[1], enemyMinionInfo[2], enemyMinionInfo[3], 0, 0, 0, 0, 0, 0));
      }
      alert(that.enemyMinions.length);
    });   

}

未捕获的TypeError：无法设置未定义的属性“0”

1 个答案: