public void BindToNullable() { System.Web.UI.WebControls.TextBox textBox = new System.Web.UI.WebControls.TextBox(); textBox.Text = string.Empty; BindToNullable_TestEntity entity = new BindToNullable_TestEntity(); new SimpleExpressionBinding("Text", "SortOrder").BindSourceToTarget(textBox, entity, null); Assert.IsNull(entity.SortOrder); }