Visual Studio 2010
静态构造函数用于初始化任何 数据，或用于执行仅需执行一次的特定操作。 在创建第一个实例或引用任何静态成员之前，将自动调用静态构造函数。
C#
class SimpleClass{ // Static variable that must be initialized at run time. static readonly long baseline; // Static constructor is called at most one time, before any // instance constructor is invoked or member is accessed. static SimpleClass() { baseline = DateTime.Now.Ticks; }} 静态构造函数具有以下特点：
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静态构造函数既没有访问修饰符，也没有参数。
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在创建第一个实例或引用任何静态成员之前，将自动调用静态构造函数来初始化。
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无法直接调用静态构造函数。
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在程序中，用户无法控制何时执行静态构造函数。
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静态构造函数的典型用途是：当类使用日志文件时，将使用这种构造函数向日志文件中写入项。
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静态构造函数在为非托管代码创建包装类时也很有用，此时该构造函数可以调用 LoadLibrary 方法。
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如果静态构造函数引发异常，运行时将不会再次调用该构造函数，并且在程序运行所在的应用程序域的生存期内，类型将保持未初始化。
在此示例中，类 Bus 有一个静态构造函数。 创建 Bus 的第一个实例（bus1）时，将调用该静态构造函数来初始化该类。 输出示例验证了即使创建 Bus 的两个实例，该静态构造函数也仅运行一次，并且在实例构造函数运行之前运行。
C#
public class Bus { // Static variable used by all Bus instances. // Represents the time the first bus of the day starts its route. protected static readonly DateTime globalStartTime; // Property for the number of each bus. protected int RouteNumber { get; set; } // Static constructor to initialize the static variable. // It is invoked before the first instance constructor is run. static Bus() { globalStartTime = DateTime.Now; // The following statement produces the first line of output, // and the line occurs only once. Console.WriteLine("Static constructor sets global start time to {0}", globalStartTime.ToLongTimeString()); } // Instance constructor. public Bus(int routeNum) { RouteNumber = routeNum; Console.WriteLine("Bus #{0} is created.", RouteNumber); } // Instance method. public void Drive() { TimeSpan elapsedTime = DateTime.Now - globalStartTime; // For demonstration purposes we treat milliseconds as minutes to simulate // actual bus times. Do not do this in your actual bus schedule program! Console.WriteLine("{0} is starting its route {1:N2} minutes after global start time {2}.", this.RouteNumber, elapsedTime.TotalMilliseconds, globalStartTime.ToShortTimeString()); } } class TestBus { static void Main() { // The creation of this instance activates the static constructor. Bus bus1 = new Bus(71); // Create a second bus. Bus bus2 = new Bus(72); // Send bus1 on its way. bus1.Drive(); // Wait for bus2 to warm up. System.Threading.Thread.Sleep(25); // Send bus2 on its way. bus2.Drive(); // Keep the console window open in debug mode. System.Console.WriteLine("Press any key to exit."); System.Console.ReadKey(); } } /* Sample output: Static constructor sets global start time to 3:57:08 PM. Bus #71 is created. Bus #72 is created. 71 is starting its route 6.00 minutes after global start time 3:57 PM. 72 is starting its route 31.00 minutes after global start time 3:57 PM. */