InvokePattern
InvokePattern是UIA中最常用的Pattern之一，WPF和Winform中的button控件都支持InvokePattern。
对InvokePattern的Invoke()方法的调用应立即返回，没有出现阻止情况。但是，此行为完全依赖于 Microsoft UI 自动化提供程序实现。在调用 Invoke() 会引起阻止问题（如Winform中的模式对话框，但是WPF中的对话框的处理方式和winform不同，所以可以使用Invoke()方法来操作WPF中的模式对话框，因为WPF中的模式对话框不会出现阻止的问题）的情况下，要调用此方法，则需要另起线程来操作。
Code
using System;
using System.Text;
using System.Diagnostics;
using System.Threading;
using System.Windows.Automation; namespace UIATest
{
class Program
{
static void Main(string[] args)
{
Process process = Process.Start(@"F:\CSharpDotNet\AutomationTest\ATP\WpfApp\bin\Debug\WpfApp.exe");
int processId = process.Id;
AutomationElement element = FindElementById(processId, "button1");
InvokePattern currentPattern = GetInvokePattern(element);
currentPattern.Invoke();
} /// <summary>
/// Get the automation elemention of current form.
/// </summary>
/// <param name="processId">Process Id</param>
/// <returns>Target element</returns>
public static AutomationElement FindWindowByProcessId(int processId)
{
AutomationElement targetWindow = null;
int count = 0;
try
{
Process p = Process.GetProcessById(processId);
targetWindow = AutomationElement.FromHandle(p.MainWindowHandle);
return targetWindow;
}
catch (Exception ex)
{
count++;
StringBuilder sb = new StringBuilder();
string message = sb.AppendLine(string.Format("Target window is not existing.try #{0}", count)).ToString();
if (count > 5)
{
throw new InvalidProgramException(message, ex);
}
else
{
return FindWindowByProcessId(processId);
}
}
}
/// <summary>
/// Get the automation element by automation Id.
/// </summary>
/// <param name="windowName">Window name</param>
/// <param name="automationId">Control automation Id</param>
/// <returns>Automatin element searched by automation Id</returns>
public static AutomationElement FindElementById(int processId, string automationId)
{
AutomationElement aeForm = FindWindowByProcessId(processId);
AutomationElement tarFindElement = aeForm.FindFirst(TreeScope.Descendants,
new PropertyCondition(AutomationElement.AutomationIdProperty, automationId));
return tarFindElement;
}
#region InvokePattern helper
/// <summary>
/// Get InvokePattern
/// </summary>
/// <param name="element">AutomationElement instance</param>
/// <returns>InvokePattern instance</returns>
public static InvokePattern GetInvokePattern(AutomationElement element)
{
object currentPattern;
if (!element.TryGetCurrentPattern(InvokePattern.Pattern, out currentPattern))
{
throw new Exception(string.Format("Element with AutomationId '{0}' and Name '{1}' does not support the InvokePattern.",
element.Current.AutomationId, element.Current.Name));
}
return currentPattern as InvokePattern;
} #endregion
}
} |
