sample15.cs

C#函数手册

namespace apiBook
{
	using System;
	using System.Data;
	using System.IO;
	public class TestClass 
	{ 
		public static void Main()
		{
			TestClass test=new TestClass();
			DataTable testDT = new DataTable("student");
			DataColumn testDC = new DataColumn("Id",Type.GetType("System.Int32"));
			testDT.Columns.Add(testDC);
			testDC = new DataColumn("Name",Type.GetType("System.String"));
			testDT.Columns.Add(testDC);
			testDC = new DataColumn("School",Type.GetType("System.String"));
			testDT.Columns.Add(testDC);
			DataColumn[] testDCA = new DataColumn[2];
			testDCA[0] = testDT.Columns["Id"];
			testDCA[1] = testDT.Columns["Name"];
			UniqueConstraint testUC = new UniqueConstraint("IdNameConstraint", testDCA);
			testDT.Constraints.Add(testUC);	  foreach(UniqueConstraint uc in testDT.Constraints)
											  {
												  if(testUC.Equals(uc))
													  //使用Equals方法判断当前的
													  //UniqueConstraint对象是否与指定对象相同
												  {
													  Console.WriteLine("识别到主键约束："+
														  testUC.ConstraintName);
													  Console.WriteLine("该约束的哈希代码："+
														  testUC.GetHashCode());
													  //使用GetHashCode方法获取
													  //UniqueConstraint对象的此实例的哈希代码
												  }
											  }
			Console.ReadLine();
		}	
	}
}