下載/打開Excel文件與FileResult MVC4不工作

Question

我想在Excel中使用FileResult對象在本地磁盤上打開Excel文件。當我點擊文件打開時，它下載與我的ActionResult（WTF？）命名相同的文件，當點擊下載的文件時，它會彈出「選擇程序」窗口。如果我選擇Excel，它會打開它，但我錯過了什麼使它下載作爲Excel文件，並打開它沒有額外的步驟？以下是我打開文件的switch語句。由於

public ActionResult GetFile(string path) 
    { 

     string extension = new FileInfo(path).Extension; 
     if (extension != null || extension != string.Empty) 
     { 
      switch (extension) 
      { 
       case ".pdf": 
        return File(path, "application/pdf"); 
       case ".txt": 
        return File(path, "application/plain"); 
       case ".jpeg": 
        return File(path, "application/jpeg"); 
       case ".doc": 
        return File(path, "application/msword"); 
       case ".docx": 
        return File(path, "application/msword"); 
       case ".xls": 
        return File(path, "application/msexcel"); 
       case ".xlsx": 
        return File(path, "application/msexcel"); 
       default: 
        return File(path, "application/octet-stream"); 
      } 
     } 
     return View("Index"); 
    } 

Answer 1

檢查：

case ".xls": 
    return File(path, "application/vnd.ms-excel"); 
case ".xlsx": 
    return File(path, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"); 

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