Step by step to Control Validation:- Add a Form
- Go to Form Property window.
- Disable AutoValidate .
- Add a Text Box in the Form.
- Add a Button in the Form.
- Verify CausesValidation is true.
The following code add into Validating Event of TextBox and Click event of Button.if (textBox1.Text.Length == 0)
{
e.Cancel = true;
}
else
{
e.Cancel = false;
} TextBox Validating Event: if (this.ValidateChildren())
{
MessageBox.Show("Validation succeeded!");
}
else
{
MessageBox.Show("Validation failed.");
}