WinForms: Implementing Custom Validation Logic for Multiple TextBox Inputs
I'm confused about I'm trying to figure out I'm working on a WinForms application where I have multiple TextBox controls that need to validate input according to specific rules before allowing the user to proceed... I've implemented some basic validation, but I'm running into issues when the user inputs invalid data and attempts to switch focus to another control. The current approach I'm using shows a message box for each invalid TextBox, which can be quite disruptive. I've tried attaching event handlers for the `Validating` event of each TextBox, but the validation logic is still not centralized or efficient, especially when handling multiple inputs. Here’s a snippet of what I have so far: ```csharp private void textBox1_Validating(object sender, CancelEventArgs e) { if (string.IsNullOrWhiteSpace(textBox1.Text)) { MessageBox.Show("TextBox 1 want to be empty."); e.Cancel = true; } } private void textBox2_Validating(object sender, CancelEventArgs e) { if (textBox2.Text.Length < 5) { MessageBox.Show("TextBox 2 must be at least 5 characters."); e.Cancel = true; } } private void textBox3_Validating(object sender, CancelEventArgs e) { if (!Regex.IsMatch(textBox3.Text, "^[a-zA-Z]+$") ) { MessageBox.Show("TextBox 3 must contain only letters."); e.Cancel = true; } } ``` While this works, I find it cumbersome to maintain as I add more TextBoxes. What’s the best practice for implementing a centralized validation approach in this scenario? Any suggestions on how to improve the user experience during validation? I'll be grateful for any design patterns or techniques that can help. I'm currently using .NET Framework 4.8, and my goal is to minimize interruptions and improve the overall validation flow. I'm on Ubuntu 22.04 using the latest version of Csharp. Any help would be greatly appreciated!