C WinForm development opens the txt file and displays it in RichTextBox. Add the function of saving after editing

Add one openFileDialog Components , Then write the corresponding function ： Here is a pre-defined RichTextBox rtbInfo;

private void OpenFromFile()
        {
            openFileDialog.Filter = "txt Format （*.txt）|*.txt| All the files |*.*";
            openFileDialog.Title = " open ";
            openFileDialog.FileName = pname;// The path of the file to open 
            rtbInfo.Clear();// First clear Show new content again 
            rtbInfo.LoadFile(openFileDialog.FileName, RichTextBoxStreamType.PlainText); // open       
            rtbInfo.Show();// Show 
         
        }

This will open and display txt file .

Here is how to save by clicking ：

private void SaveToFile()
        {
            //saveFileDialog.InitialDirectory = pname;// Set the default directory for saving 
            saveFileDialog.FileName = pname;
            saveFileDialog.Filter = "txt files(*.txt)|*.txt|all files(*.*)|*.*";
            saveFileDialog.FilterIndex = 1;// The default display save type is TXT
            saveFileDialog.RestoreDirectory = true;
            rtbInfo.SaveFile(saveFileDialog.FileName, RichTextBoxStreamType.PlainText);            
        }

Directly use a click event to call the function to save the event .