打破了JavaScript的嵌套async.each环路而是继续主循环 [英] Break out of javascript nested async.each loop but continue main loop

问题描述

我有对象的数组的数组称为recipesArray。

  recipesArray = [[{名=配方名，URL =htt​​p://recipeurl.com}，
                   {NAME =其他尼姆，URL =htt​​p://adifferenturl.com}，
                   {NAME =另一个配方，URL =htt​​p://anotherurl.com}]，                   [{名称=配方名，URL =htt​​p://recipeurl.com}，
                   {NAME =其他尼姆，URL =htt​​p://adifferenturl.com}，
                   {NAME =另一个配方，URL =htt​​p://anotherurl.com}]，                   [{名称=配方名，URL =htt​​p://recipeurl.com}，
                   {NAME =其他尼姆，URL =htt​​p://adifferenturl.com}，
                   {NAME =另一个配方，URL =htt​​p://anotherurl.com}]
 

我要打破这个嵌套async.each循环，而是继续在主async.each循环。

  //主async.each
async.each（配方，功能（子数组，调用callback1）{
   //嵌套async.each
   async.each（子阵列功能（theCurrentRecipe，callback2）{
      checkHREFS（theCurrentRecipe，功能（thisRecipe）{
         如果（我有一个条件在这里'）{
            //打破这个嵌套async.each的，
            //而是继续主要async.each。
         }其他{
            //继续
         }
         callback2（）;
      }）;
   }，调用callback1）;
}，功能（错误）{
如果（ERR）{
   返回console.error（ERR）;   //成功，所有配方迭代
}）;
 

解决方案

一种方式是修改的最终回调内部各（）来检查与指示你早日打破了一个特殊的属性Error对象而且它不是一个真正的错误。然后里面的条件，传递一个错误的对象，与该属性设置，回调。

例如：

  //主async.each
async.each（配方，功能（子数组，调用callback1）{
  //嵌套async.each
  async.each（子阵列功能（theCurrentRecipe，callback2）{
    checkHREFS（theCurrentRecipe，功能（thisRecipe）{
      如果（我有一个条件在这里'）{
        //打破这个嵌套async.each的，
        //而是继续主要async.each。
        VAR fakeErr =新的Error（）;
        fakeErr.break = TRUE;
        返回callback2（fakeErr）;
      }
      //继续
      callback2（）;
    }）;
  }，功能（错误）{
    如果（ERR和放大器;＆安培; err.break）
      调用callback1（）;
    其他
      调用callback1（ERR）;
  }）;
}，功能（错误）{
  如果（ERR）
    返回console.error（ERR）;  //成功，所有配方迭代
}）;
 

I have an array of arrays of objects called recipesArray.

recipesArray = [  [{name = "the recipe name", url = "http://recipeurl.com"},
                   {name = "the other neame", url = "http://adifferenturl.com"},
                   {name = "another recipe", url = "http://anotherurl.com"}],

                   [{name = "the recipe name", url = "http://recipeurl.com"},
                   {name = "the other neame", url = "http://adifferenturl.com"},
                   {name = "another recipe", url = "http://anotherurl.com"}],

                   [{name = "the recipe name", url = "http://recipeurl.com"},
                   {name = "the other neame", url = "http://adifferenturl.com"},
                   {name = "another recipe", url = "http://anotherurl.com"}] ]

I want to break out of this nested async.each loop, but continue the main async.each loop.

// main async.each
async.each(recipes, function(subArray, callback1) {
   // nested async.each
   async.each(subArray, function(theCurrentRecipe, callback2) {
      checkHREFS(theCurrentRecipe, function(thisRecipe) {
         if ('i have a conditional here') {
            // break out of this nested async.each, 
            // but continue the main async.each.
         } else {
            // continue
         }
         callback2();
      });
   }, callback1);
}, function(err) {
if (err) {
   return console.error(err);

   // success, all recipes iterated
});

解决方案

One way might be to modify the final callback for the inner each() to check for an Error object with a special property that indicates you're breaking out early and that it's not a real error. Then inside your conditional, pass an Error object, with that property set, to the callback.

Example:

// main async.each
async.each(recipes, function(subArray, callback1) {
  // nested async.each
  async.each(subArray, function(theCurrentRecipe, callback2) {
    checkHREFS(theCurrentRecipe, function(thisRecipe) {
      if ('i have a conditional here') {
        // break out of this nested async.each, 
        // but continue the main async.each.
        var fakeErr = new Error();
        fakeErr.break = true;
        return callback2(fakeErr);
      }
      // continue
      callback2();
    });
  }, function(err) {
    if (err && err.break)
      callback1();
    else
      callback1(err);
  });
}, function(err) {
  if (err)
    return console.error(err);

  // success, all recipes iterated
});

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