Textbox validation in a Windows Form

Question

I want to put a validation that the user always enters a value in the textbox before submiting the form. But the check that I have put allows user to enter white spaces and

Answer 1

You can make your own custom validation function. This may be very naive, but somehow it will work.

private bool WithErrors()
{
    if(textBox1.Text.Trim() == String.Empty) 
        return true; // Returns true if no input or only space is found
    if(textBox2.Text.Trim() == String.Empty)
        return true;
    // Other textBoxes.

    return false;
}

private void buttonSubmit_Click(object sender, EventArgs e)
{
    if(WithErrors())
    {
        // Notify user for error.
    }
    else
    {
        // Do whatever here... Submit
    }
}