Upload differnt types of files to different folders using Switch Case

// protected void Button1_Click(object sender, EventArgs e)
    {
        if (FileUpload1.HasFile)
        {
            uploadfiles(FileUpload1.PostedFile);
        }
        else
        {
            Label1.Text = "please select file to upload";
        }

    }

protected void uploadfiles(HttpPostedFile file)
    {
        string ext=Path.GetExtension(FileUpload1.FileName); //get the extension of the file
        string filepath;
       switch(ext)
           {
               case ".jpg":
                  filepath=Server.MapPath("./uploadimage/"); for image files
                  ViewState["filepath"] = filepath.ToString();//we store filepath in viewstate 
                   break;
               case ".png":
                   filepath = Server.MapPath("./uploadimage/");
                   ViewState["filepath"] = filepath.ToString();
                   break;
               case ".docx":
                   filepath = Server.MapPath("./uploadwordfiles/"); for word files//
                   ViewState["filepath"] = filepath.ToString();
                   break;
              
               case ".doc":
                   filepath = Server.MapPath("./uploadwordfiles/");
                   ViewState["filepath"] = filepath.ToString();
                   break;
               case ".pdf":
                   filepath = Server.MapPath("./uploadpdf/");//for pdf files
                   ViewState["filepath"] = filepath.ToString();
                   break;
               case ".jpeg":
                   filepath = Server.MapPath("./uploadimage/");
                   ViewState["filepath"] = filepath.ToString();
                   break;
                  
               default:
                   Label1.Text = "this file type is not allowed";
                   return;
           }

       // In this part of code, we will check if the  file with the same name exists in the folder.if yes,then we will execute a while loop,changing the name of the file//

       string filename = FileUpload1.FileName;
       string checkpath= ViewState["filepath"].ToString() + filename;
       string tempfilepath = "";
        if(File.Exists(checkpath))
             {
                 int counter = 2;
            while(File.Exists(checkpath))
                {
                    tempfilepath = counter.ToString() + filename;
                    checkpath= ViewState["filepath"].ToString() + tempfilepath;
                    counter++;
                }
            filename = tempfilepath;
             label2.Text = ext.ToString();
       
        Label1.Text = "this filename already exists.your file is saved with the filename" + " " + filename.ToString();
        
             }
        else
        {
          // Notify the user that the file was saved successfully.
          Label1.Text = "Your file was uploaded successfully.";
        }
        ViewState["filepath"]+= filename;
        FileUpload1.SaveAs(checkpath);

    }

Using the code above, we can decide the file path according to the file type and also change the file name if the file with the same name already exists.

Conclusion