如何只打开 a.dat 文件。 在 C#

Question

I'm trying to open a file but I want it filter out to only.dat file.

using (OpenFileDialog fileChooser = new OpenFileDialog())
{
    result = fileChooser.ShowDialog();
    fileName = fileChooser.FileName; //Get file name.
    fileChooser.Filter = "Data File|*.dat;";
    fileChooser.DefaultExt = "dat";
    fileChooser.AddExtension = true;
}

When having a OpenFileDialog in "using" the filter, defaultExt and Addextension doesn't work.

Answer 1

You should set filters before the call of "ShowDialog" method.

Answer 2

This should work.

using (var fileChooser = new OpenFileDialog())
{
    // define the filters (first description | first filter; second description ...
    fileChooser.Filter = "Data File|*.dat";
    // select the first filter
    fileChooser.FilterIndex = 1;
    fileChooser.DefaultExt = "dat";
    fileChooser.AddExtension = true;

    // show the Opendialog
    if (fileChooser.ShowDialog() == DialogResult.OK)
    {
        // get the path of specified file
        var filename = fileChooser.FileName;

        // use the filename to open the file...
    }
}