Check out example codes for "get user directory of file in c#". It will help you in understanding the concepts better.

Code Example 1

using (OpenFileDialog openFileDialog = new OpenFileDialog())
            {
                // TODO: Use LocalUser instead of Hardcode
                openFileDialog.InitialDirectory = @"C:\Users\username\Desktop"; 
                openFileDialog.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
                openFileDialog.FilterIndex = 2;
                openFileDialog.RestoreDirectory = true;

                if (openFileDialog.ShowDialog() == DialogResult.OK)
                {
                    //Get the path of specified file
                    filePath = openFileDialog.FileName;

                    //Read the contents of the file into a stream
                    var fileStream = openFileDialog.OpenFile();

                    using (StreamReader reader = new StreamReader(fileStream))
                    {
                        fileContent = reader.ReadToEnd();
                    }
                }
            }

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