我构建了一个测试箱来了解有关 Windows 窗体应用程序中的线程的知识.Silverlight 和 Java 正在提供 Dispatcher,这在更新时确实很有帮助GUI 元素.
I built a Testbox to learn something about threading in windows form applications. Silverlight and Java are providing the Dispatcher, which really helps when updating GUI Elements.
代码示例:声明类委托
public delegate void d_SingleString(string newText);
创建线程
_thread_active = true;
Thread myThread = new Thread(delegate() { BackGroundThread(); });
myThread.Start();
线程函数
private void BackGroundThread()
{
while (_thread_active)
{
MyCounter++;
UpdateTestBox(MyCounter.ToString());
Thread.Sleep(1000);
}
}
委派文本框更新
public void UpdateTestBox(string newText)
{
if (InvokeRequired)
{
BeginInvoke(new d_SingleString(UpdateTestBox), new object[] { newText });
return;
}
tb_output.Text = newText;
}
有没有办法在 BeginInvoke 方法中声明延迟声明?!
Is there a way to declare the Declaration of the Delate IN the BeginInvoke Method?!
类似
BeginInvoke(*DELEGATE DECLARATION HERE*, new object[] { newText });
非常感谢,雷特
在很多这样的情况下,最简单的方法是使用捕获的变量"在线程之间传递状态;这意味着您可以保持逻辑本地化:
In many cases like this, the simplest approach is to use a "captured variable" to pass state between the threads; this means you can keep the logic localised:
public void UpdateTestBox(string newText)
{
BeginInvoke((MethodInvoker) delegate {
tb_output.Text = newText;
});
}
如果我们期望在工作线程上调用它(很少点检查InvokeRequired
),上述内容特别有用 - 请注意,这对于任何一个 UI 都是安全的或工作线程,并允许我们在线程之间传递尽可能多或尽可能少的状态.
The above is particularly useful if we expect it to be called on the worker thread (so little point checking InvokeRequired
) - note that this is safe from either the UI or worker thread, and allows us to pass as much or as little state between the threads.
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