WPF 的 Hello World
代码如下：
1)Window1.cs

C# code

//Window1.csusing System;using System.Windows;using System.Windows.Controls; // Button et alnamespace MyFirstWpfApp {  class Window1 : Window {    public Window1() {      this.Text = "Hello, Wpf";      // Do something interesting      Button button = new Button();      button.Content = "Click me, baby, one more time!";      button.Width = 200;      button.Height = 25;      button.Click += button_Click;      this.AddChild(button);    }    void button_Click(object sender, RoutedEventArgs e) {      MessageBox.Show("You've done that before, haven't you...", "Nice!");    }  }}

2)MyApp.cs

C# code

//MyApp.csusing System;using System.Windows;namespace MyFirstWpfApp {  class MyApp : Application {    [STAThread]    static void Main(string[] args) {      MyApp app = new MyApp();      app.StartingUp += app.AppStartingUp;      app.Run(args);    }    void AppStartingUp(object sender, StartingUpCancelEventArgs e) {      // Let the Window1 initialize itself      Window window = new Window1();      window.Show();    }  }}

3)1st.csproj

C# code

<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">  <PropertyGroup>    <OutputType>winexe</OutputType>    <OutputPath>.\</OutputPath>    <Assembly>1st.exe</Assembly>  </PropertyGroup>  <ItemGroup>    <Compile Include="MyApp.cs" />    <Compile Include="Window1.cs" />    <Reference Include="System" />    <Reference Include="WindowsBase" />    <Reference Include="PresentationCore" />    <Reference Include="PresentationFramework" />  </ItemGroup>  <Import Project="$(MsbuildBinPath)\Microsoft.CSharp.targets" /></Project>

编译：MSBuild 1st.csproj

报错：
MyApp.cs(14,39): error CS0246: The type or namespace name 'StartingUpCancelEventArgs' could not be found (are you missing a using directive or an assembly reference?) [C:\tmp\1st.csproj]
Done Building Project "C:\tmp\1st.csproj" (default targets) -- FAILED.

请问：问题出在哪里？应该如何纠正？

[解决办法]
'StartingUpCancelEventArgs'

这个命名空间找不到。
[解决办法]
'StartingUpCancelEventArgs'
你在项目里用右键点出错的地方，是否能引用命名空间？
[解决办法]
没有发现命名空间，是因为你没有引入或者是没有定义，这样楼主就应该明白了吧
[解决办法]
你从这里下载吧，我吧代码传到这里了：

http://www.silverlightchina.net/resource/code/WpfApplicationDemo.rar
[解决办法]
楼主太好了

探讨

你从这里下载吧，我吧代码传到这里了：

http://www.silverlightchina.net/resource/code/WpfApplicationDemo.rar

[解决办法]
兄弟我真晕你！ 不是这样写的啦！