使用C＃的Windows Phone应用程序中的文件大小限制

Question

I am new in Windows Phone application. In my application, when uploading files it is required to add file size limit not exceeding 50kb.

Code:

public sealed class OpenFileDialog
{
    public string Filter { get; set; }

    internal static object ShowDialog()
    {
        throw new NotImplementedException();
    }
    public static object DialogResult { get; set; }
    public static string FileName { get; set; }
}

if (OpenFileDialog.ShowDialog() == System.Windows.Controls.DialogResult.OK)
{
    FileStream fs = File.OpenRead(OpenFileDialog.FileName);
    if (fs.Length > 51200)
    {
        MessageBox.Show("Image size must not exceed 50kb.");
        return;
    }
    System.Windows.Controls.Image myImage = new System.Windows.Controls.Image();
    myImage.Source = bmp;
}

but it show error,

Error:

namespace dialogresult doesn't exist in the namespace system.windows.controls(missing a assembly reference)

Anybody help me to solve this error?

Answer 1

You're attempting to use an enumeration that is part of the System.Windows.Forms namespace, and no such open file dialog exists in the Windows Phone 8 library. Without knowing more about your file access scenario, I will point out that your options would include:

• Application Isolated Storage
• Known Folders (WP 8.1 only including music, videos, photos, and SD card storage)

I'll point you to this general guide to accessing files programmatically which may take you to where you need to be specifically, but I should point out that since the most commonly accessible files on a phone device are rarely 50kb or less in size, we likely need more information about your use case.