UiaControlsTest.WpfAppTests.Native_CaretPositionPatternSmokeTest C# (CSharp) Method

        public void Native_CaretPositionPatternSmokeTest()
        {
            CaretPositionPattern.Initialize();
            var cps = (ICaretPositionPattern)_nAdvancedTextBoxElement.GetCurrentPattern(CaretPositionPattern.Pattern.Id);
            Assert.IsNotNull(cps);

            // sanity check: intial selection is none, there's no text after all
            Assert.AreEqual(0, cps.CurrentSelectionStart);
            Assert.AreEqual(0, cps.CurrentSelectionLength);

            // enter "abcd" and select central part of it - "bc"
            NSetTextAndSelection("abcd", 1, 2);
            Assert.AreEqual(1, cps.CurrentSelectionStart);
            Assert.AreEqual(2, cps.CurrentSelectionLength);

            // validate that selected text retrieved from TextPattern changed as expected
            var text = (IUIAutomationTextPattern)_nAdvancedTextBoxElement.GetCurrentPattern(TextPattern.Pattern.Id);
            var selectionArray = text.GetSelection();
            var selection = selectionArray.GetElement(0);
            var selectedString = selection.GetText(-1);
            Assert.AreEqual("bc", selectedString);
        }