Convert String To Lower Upper Proper cases

private void Button1_Click(object sender, System.EventArgs e)
{
// TextInfo Class available in System.Globalization namespace;

TextInfo t = new CultureInfo("en-US",false).TextInfo;

//TextInfo Class Defines properties and behaviors, such as casing,
//that are specific to a writing system
Response.Write("LowerCase :"+t.ToLower(TextBox1.Text)+"
ProperCase :"

                                               +t.ToTitleCase(TextBox1.Text)+"
UpperCase :"

                                               +t.ToUpper(TextBox1.Text));
}