用StreamReader逐行读取文件

Question

I am trying to read a simple text file line by line in Windows 8 C# file with StreamReader. I tried many solutions but non of it worked. Sometimes the file is read and sometimes it's not(the class is empty, only nulls). If the program is running it's never working but when I set up a debugger and use it to go line by line sometimes it works. Why is that? That's the source:

public async void read(string fileName)
    {

        string File = Path.Combine(Package.Current.InstalledLocation.Path, "myfolder", fileName);

        StorageFolder folder = await StorageFolder.GetFolderFromPathAsync(Path.GetDirectoryName(File));

        Stream s = await folder.OpenStreamForReadAsync(Path.GetFileName(File));
        StreamReader streamReader = new StreamReader(s);

        myClass.name = streamReader.ReadLine();
        myClass.desc = streamReader.ReadLine();
        myClass.number = int.Parse(streamReader.ReadLine());
        myClass.house = new House[myClass.number];

        for (int i = 0; i < myClass.number; i++)
        {
            myClass.house[i] = new House();
            myClass.house[i].name = streamReader.ReadLine();
            myClass.house[i].size = double.Parse(streamReader.ReadLine());
        }  
    }

Answer 1

You should only use async void if the function is an event handler (eg button press). Generally, you should use async Task instead.

Change your method signature from void to Task :

public async Task read(string fileName)

Then from your calling code, await it:

await yourclass.read("c:\\my_filename.txt");