将MSDN示例从c#转换为c++ / cli

本文关键字：c++ cli 转换 MSDN | 更新日期: 2023-09-27 17:49:34

这是一个来自Microsoft(MSDN)的代码样本(构建sql依赖应用程序)，你能帮我把这个代码从c#翻译成c++/CLI吗，我一直在尝试，但我不是很擅长c++。

private void dependency_OnChange(
   object sender, SqlNotificationEventArgs e)
{
    // This event will occur on a thread pool thread.
    // Updating the UI from a worker thread is not permitted.
    // The following code checks to see if it is safe to
    // update the UI.
    ISynchronizeInvoke i = (ISynchronizeInvoke)this;
    // If InvokeRequired returns True, the code
    // is executing on a worker thread.
    if (i.InvokeRequired)
    {
        // Create a delegate to perform the thread switch.
        OnChangeEventHandler tempDelegate =
            new OnChangeEventHandler(dependency_OnChange);
        object[] args = { sender, e };
        // Marshal the data from the worker thread
        // to the UI thread.
        i.BeginInvoke(tempDelegate, args);
        return;
    }
    // Remove the handler, since it is only good
    // for a single notification.
    SqlDependency dependency =
        (SqlDependency)sender;
    dependency.OnChange -= dependency_OnChange;
    // At this point, the code is executing on the
    // UI thread, so it is safe to update the UI.
    ++changeCount;
    label1.Text = changeCount;
}

将MSDN示例从c#转换为c++ / cli

这是我的快速尝试:

private void dependency_OnChange(
   System::Object^ sender, SqlNotificationEventArgs^ e)
{
    // This event will occur on a thread pool thread.
    // Updating the UI from a worker thread is not permitted.
    // The following code checks to see if it is safe to
    // update the UI.
    ISynchronizeInvoke^ i = this;
    // If InvokeRequired returns True, the code
    // is executing on a worker thread.
    if (i->InvokeRequired)
    {
        // Create a delegate to perform the thread switch.
        OnChangeEventHandler^ tempDelegate =
            gcnew OnChangeEventHandler(this, &Form1::dependency_OnChange);
        cli::array<System::Object^>^ args = gcnew cli::array<System::Object^>(2);
        args[0] = sender;
        args[1] = e;
        // Marshal the data from the worker thread
        // to the UI thread.
        i->BeginInvoke(tempDelegate, args);
        return;
    }
    // Remove the handler, since it is only good
    // for a single notification.
    SqlDependency^ dependency = safe_cast<SqlDependency^>(sender);
    dependency->OnChange -= gcnew OnChangeEventHandler(this, &Form1::dependency_OnChange);
    // At this point, the code is executing on the
    // UI thread, so it is safe to update the UI.
    ++changeCount;
    label1->Text = changeCount.ToString();
}

编译c#示例源代码，然后使用Reflector将程序集反编译为mc++(托管c++)。

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