C# openfiledialog filter application example

Click Browse to open a file selection dialog box in the software, which is realized by the OpenFileDialog control. Of course, OpenFileDialog itself does not have a browser, and a button must be added as the button to open the file selection dialog box.

There are not many properties of the OpenFileDialog control in C#. Usually there are only a few properties that need to be set, such as InitialDirectory, RestoreDirectory, Filter, FilterIndex, Multiselect, etc. Let's look at a specific application example.

C# openfiledialog filter application example:

1. Drag an OpenFileDialog control to the Form and keep the default name openFileDialog1(or change it to another name).

2. Drag another TextBox control to the Form, keep the default name textBox1, and drag it longer to show the long path.

3. Finally drag a Button control to the Form, keep the default name button1, change its Text property to "Browse", double-click button1 to open the code-behind file.

4. Add code(complete code) in the private void button1_Click(object sender, EventArgs e) method:

private void button1_Click(object sender, EventArgs e)
       {
              openFileDialog1.InitialDirectory = @"C:\";//Initial display directory

       //Whether to locate the last opened directory for the next open dialog
              openFileDialog1.RestoreDirectory = true;

       //Filter file types
              openFileDialog1.Filter = "Text file (*.txt)|*.txt|All files (*.*)|*.*";

       //FilterIndex is associated with Filter and is used to set the file type displayed by default
              openFileDialog1.FilterIndex = 1;//The default is 1, the file type displayed by default is *.txt; if it is set to 2, the file type displayed by default is *.*

       if (openFileDialog1.ShowDialog() == DialogResult.OK)
              {
                     //Assign the selected file to the textbox
                     textBox1.Text = openFileDialog1.FileName;
              }
       }

The above code passed the test in Visual Studio 2019, and the running effect is as follows: