How to mention string value that is not case sensitive

Question

Hi, I want to declare a string value in a WPF application.
Example:
private void button1_Click(object sender, RoutedEventArgs e)
{
if (textBox1.Text == "Name")
{
label1.Content = "This is " + textBox1.Text;
}
  }
If the user enter NAME/ name/ Name the if condition should apply and give the corresponding output
ie. label1 should display   This is Name/ NAME/etc.