I created the editor inheriting the TextBox.

The editor loads the data from the file like below.

```
public Editor()
{
    this.Text = File.ReadAllText(fileName);
}

```

The above code works well but the changes of the editor do not apply because not be bound with the file.

In other words, although I change the content of the editor then the changes do not apply to the file.

To do this, I need to write additional code as below.

```
File.WriteAllText(fileName, content);

```

The problem is I don't know where to put the above code.

If I put the above code onto the `TextChanged` event handler then the performance of the editor is lower.

But I don't know the suitable position to put the above code except for `TextChanged` event handler.

Is there a formulaic way to solve this problem?