AngularJS承諾數組

Question

任何人都可以幫助我一些角度的承諾？我有以下函數應該在文件對象數組中進行迭代，然後上傳每個文件對象。在每次迭代期間，承諾對象被推送到一個數組promises。在我的upload函數中，我有一個cycle函數，附帶一個.then()函數，直到所有promise對象都解析完畢才能調用函數。我認爲我的代碼看起來是正確的，但它不正確。圖像上傳，但cycle(files).then()立即被調用，而不是一旦promises陣列解決。

function upload(files) { 
    var uploadCount = files.length; 
    function cycle(files) { 
     var promises = []; 
     for (var i = 0; i < files.length; i++) { 
      var deferred = $q.defer(); 
      promises.push(deferred); 
      var file = files[i]; 
      Upload.upload({ 
       url: '/photos.json', 
       file: file 
      }).success(function(){ 
       $scope.progressCurrentCount += 1; 
       deferred.resolve(); 
      }); 
     }; 
     return $q.all(promises); 
    }; 

    cycle(files).then(function(result) { 
     if(uploadCount > 1) { 
      $scope.lastAction = 'uploaded ' + uploadCount + ' photos'; 
     } else { 
      $scope.lastAction = 'uploaded ' + uploadCount + ' photo'; 
     } 
     $scope.showSuccessModal = true; 
     $scope.uploading = false; 
     $scope.failedUploads = []; 
     $scope.newPhotos = { 
      token: $scope.token, 
      files: undefined 
     }; 
     photoUploadBtn.removeClass('disabled'); 
    }) 
}; 

最後的工作代碼*

，而不是設置var deferred = $q.defer();推deferred.promise到promises數組，然後在我的.success()的回調，這是行不通的解決deferred，我只是把我的Upload.upload()功能，無需將.success()回調爲promises，然後將其傳遞給$q.all()，這樣做完全解除。

function upload(files) { 
    var uploadCount = files.length; 
    function cycle(files) { 
     var promises = []; 
     for (var i = 0; i < files.length; i++) { 
      var file = files[i]; 
      var promise = Upload.upload({ 
       url: '/photos.json', 
       file: file 
      }); 
      promises.push(promise); 
     }; 
     return $q.all(promises); 
    }; 

    cycle(files).then(function(result) { 
     if(uploadCount > 1) { 
      $scope.lastAction = 'uploaded ' + uploadCount + ' photos'; 
     } else { 
      $scope.lastAction = 'uploaded ' + uploadCount + ' photo'; 
     }; 
     $scope.showSuccessModal = true; 
     $scope.uploading = false; 
     $scope.failedUploads = []; 
     $scope.newPhotos = { 
      token: $scope.token, 
      files: undefined 
     }; 
     photoUploadBtn.removeClass('disabled'); 
     getPhotos(q); 
    }) 
}; 

Answer 1

必須按一個承諾，而不是推遲，到promises陣列：

promises.push(deferred.promise); 

它幫助，如果你仔細想想這樣的：

• 的承諾是讀 - 僅限於您想要返回給消費者的對象
• 延遲是該只讀承諾的修飾符，並且您想保留自己