ddbview.cs

Csharp网络应用案例导航 Csharp网络应用案例导航

			// 
			this.tabRem.Controls.AddRange(new System.Windows.Forms.Control[] {
																				 this.radioRem4,
																				 this.radioRem3,
																				 this.radioRem2,
																				 this.radioRem1,
																				 this.dataGridRem});
			this.tabRem.Location = new System.Drawing.Point(4, 24);
			this.tabRem.Name = "tabRem";
			this.tabRem.Size = new System.Drawing.Size(593, 384);
			this.tabRem.TabIndex = 1;
			this.tabRem.Text = "远程数据库查询";
			// 
			// radioRem4
			// 
			this.radioRem4.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioRem4.Location = new System.Drawing.Point(451, 332);
			this.radioRem4.Name = "radioRem4";
			this.radioRem4.Size = new System.Drawing.Size(121, 29);
			this.radioRem4.TabIndex = 7;
			this.radioRem4.Text = "开发商信息";
			// 
			// radioRem3
			// 
			this.radioRem3.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioRem3.Location = new System.Drawing.Point(310, 332);
			this.radioRem3.Name = "radioRem3";
			this.radioRem3.Size = new System.Drawing.Size(141, 29);
			this.radioRem3.TabIndex = 6;
			this.radioRem3.Text = "广州楼盘信息";
			// 
			// radioRem2
			// 
			this.radioRem2.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioRem2.Location = new System.Drawing.Point(170, 332);
			this.radioRem2.Name = "radioRem2";
			this.radioRem2.Size = new System.Drawing.Size(140, 29);
			this.radioRem2.TabIndex = 5;
			this.radioRem2.Text = "上海楼盘信息";
			// 
			// radioRem1
			// 
			this.radioRem1.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioRem1.Checked = true;
			this.radioRem1.Location = new System.Drawing.Point(18, 332);
			this.radioRem1.Name = "radioRem1";
			this.radioRem1.Size = new System.Drawing.Size(142, 29);
			this.radioRem1.TabIndex = 4;
			this.radioRem1.TabStop = true;
			this.radioRem1.Text = "北京楼盘信息";
			// 
			// tabJoin
			// 
			this.tabJoin.Controls.AddRange(new System.Windows.Forms.Control[] {
																				  this.radioJoin2,
																				  this.radioJoin1,
																				  this.dataGridJoin});
			this.tabJoin.Location = new System.Drawing.Point(4, 24);
			this.tabJoin.Name = "tabJoin";
			this.tabJoin.Size = new System.Drawing.Size(593, 384);
			this.tabJoin.TabIndex = 2;
			this.tabJoin.Text = "联合数据查询";
			// 
			// radioJoin2
			// 
			this.radioJoin2.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioJoin2.Enabled = false;
			this.radioJoin2.Location = new System.Drawing.Point(10, 341);
			this.radioJoin2.Name = "radioJoin2";
			this.radioJoin2.Size = new System.Drawing.Size(562, 28);
			this.radioJoin2.TabIndex = 6;
			this.radioJoin2.Text = "在上海查询信誉为100的地产开发商在三地开发的所有地产信息";
			// 
			// radioJoin1
			// 
			this.radioJoin1.Anchor = (System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left);
			this.radioJoin1.Checked = true;
			this.radioJoin1.Enabled = false;
			this.radioJoin1.Location = new System.Drawing.Point(10, 313);
			this.radioJoin1.Name = "radioJoin1";
			this.radioJoin1.Size = new System.Drawing.Size(562, 28);
			this.radioJoin1.TabIndex = 5;
			this.radioJoin1.TabStop = true;
			this.radioJoin1.Text = "在广州查询上海楼盘每平米大于5000的开发商的信息";
			// 
			// DdbView
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(8, 18);
			this.ClientSize = new System.Drawing.Size(619, 483);
			this.Controls.AddRange(new System.Windows.Forms.Control[] {
																		  this.tabJoinDS,
																		  this.btnCreDB,
																		  this.InitialButton,
																		  this.Createbutton,
																		  this.BtClose,
																		  this.Qbutton});
			this.Menu = this.mainMenu1;
			this.Name = "DdbView";
			this.Text = "远程分布式数据库查询系统";
			this.Load += new System.EventHandler(this.DdbView_Load);
			((System.ComponentModel.ISupportInitialize)(this.dataGridLoc)).EndInit();
			((System.ComponentModel.ISupportInitialize)(this.dataGridRem)).EndInit();
			((System.ComponentModel.ISupportInitialize)(this.dataGridJoin)).EndInit();
			this.tabJoinDS.ResumeLayout(false);
			this.tabLoc.ResumeLayout(false);
			this.tabRem.ResumeLayout(false);
			this.tabJoin.ResumeLayout(false);
			this.ResumeLayout(false);

		}
		#endregion

		/// <summary>
		/// The main entry point for the application.
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new DdbView());
		}

	
		private void OnQuery(object sender, System.EventArgs e)
		{
			try
			{
				DataSet ds1;
				string temp=((DbServer)LocalDbServer).GetId();
				//如果现在查询本地数据库
				if(tabJoinDS.SelectedIndex==0)
				{
					//如果是查询本地楼盘信息
					if(radioLoc1.Checked==true)
					{
						ds1=((DbServer)LocalDbServer).Query(temp,"select * from RealEstate");
						dataGridLoc.DataSource=ds1;
						dataGridLoc.DataMember="Result";
					}
					else
					{
						//这时查询地产商信息，但是只要北京才可以
						ds1=((DbServer)LocalDbServer).Query(temp,"select * from Developer");
						dataGridLoc.DataSource=ds1;
						dataGridLoc.DataMember="Result";
					}
				}
				else if(tabJoinDS.SelectedIndex==1)
				{
					//这时应查询远程数据库
					if(radioRem1.Checked==true)
					{
						ds1=((DbServer)LocalDbServer).Query("北京","select * from RealEstate");
						dataGridRem.DataSource=ds1;
						dataGridRem.DataMember="Result";
					}
					else if(radioRem2.Checked==true)
					{
						ds1=((DbServer)LocalDbServer).Query("上海","select * from RealEstate");
						dataGridRem.DataSource=ds1;
						dataGridRem.DataMember="Result";
					}
					else if(radioRem3.Checked==true)
					{
						ds1=((DbServer)LocalDbServer).Query("广州","select * from RealEstate");
						dataGridRem.DataSource=ds1;
						dataGridRem.DataMember="Result";
					}
					else
					{
						ds1=((DbServer)LocalDbServer).Query("北京","select * from Developer");
						dataGridRem.DataSource=ds1;
						dataGridRem.DataMember="Result";
					}
				}
				else
				{
					//这时连结三地一起查询，但是只能在上海或广州才成
					if(radioJoin1.Checked==true)
					{
						//在广州查询上海楼盘每平米大于5000的开发商的信息
						//首先查出上海楼盘价大于5000的楼盘及开发商，并传到北京的机器上
						string t1=((DbServer)LocalDbServer).CreateTempTable("上海","北京","select RealName,RealDev from RealEstate where RealPrice>5000");
						
						//然后在北京机器上作连接操作，并把结果传回给广州
						string[] ProjectAttributes={t1+".RealName","Developer.RealDev","Developer.DevAdd","Developer.DevTel","Developer.DevFame"};
						string JoinString=((DbServer)LocalDbServer).JoinString(t1,"Developer",ProjectAttributes,"RealDev");
						string t2=((DbServer)LocalDbServer).CreateTempTable("北京",JoinString);

						//显示出结果
						ds1=((DbServer)LocalDbServer).Query("广州","select * from "+t2);
						dataGridJoin.DataSource=ds1;
						dataGridJoin.DataMember="Result";


					}
					else
					{
						//在上海查询信誉为100的地产开发商在三地开发的所有地产信息
						//首先在北京的机器上查出信誉为100的地产开发商存在北京并传到上海、广州
						string t1=((DbServer)LocalDbServer).CreateTempTable("北京","select RealDev from Developer where DevFame=100");
						string t2=((DbServer)LocalDbServer).CreateTempTable("北京","北京","select RealDev from Developer where DevFame=100");
						string t3=((DbServer)LocalDbServer).CreateTempTable("北京","广州","select RealDev from Developer where DevFame=100");
						
						//然后分别在三地作连接，并把结果传回给上海
						string[] ProjectAttributes={"RealEstate.RealDev","RealEstate.RealName","RealEstate.RealAdd","RealEstate.RealPrice"};
						string JoinString=((DbServer)LocalDbServer).JoinString(t1,"RealEstate",ProjectAttributes,"RealDev");
						string t4=((DbServer)LocalDbServer).CreateTempTable("上海",JoinString);
						JoinString=((DbServer)LocalDbServer).JoinString(t2,"RealEstate",ProjectAttributes,"RealDev");
						string t5=((DbServer)LocalDbServer).CreateTempTable("北京",JoinString);
						JoinString=((DbServer)LocalDbServer).JoinString(t3,"RealEstate",ProjectAttributes,"RealDev");
						string t6=((DbServer)LocalDbServer).CreateTempTable("广州",JoinString);
						//将三个结果合起来
						string t7=((DbServer)LocalDbServer).HMergeTable(t4,t5);
						string t8=((DbServer)LocalDbServer).HMergeTable(t6,t7);


						//显示出结果
						ds1=((DbServer)LocalDbServer).Query("上海","select * from "+t8);
						dataGridJoin.DataSource=ds1;
						dataGridJoin.DataMember="Result";
					}
					
				}



			}

				///无法获得则捕捉异常，异常情况有可能是：指定的url地址不可达或者指定获得的对象定义不对
			catch( NullReferenceException nullExp )
			{
				MessageBox.Show( "The url for the object is invalid " + nullExp.Message );
			}
			catch( RemotingException remExp )
			{
				MessageBox.Show( "The object type is not defined properly, it needs to be derived for a remoting class " + remExp.Message );
			}
		}

		private void OnClose(object sender, System.EventArgs e)
		{		
			Dispose(true);
		}

		private void Createbutton_Click(object sender, System.EventArgs e)
		{
		
		}

		private void InitialButton_Click(object sender, System.EventArgs e)
		{
			try
			{

				//get the Server Object:
				
				LocalDbServer = ( DbServer )Activator.GetObject(typeof(DbServer),"tcp://localhost:"+port+"/DDB");
				
				//初始化并返回本机所在地(北京、上海、广州)
				string id=((DbServer)LocalDbServer).Initial();

				//				((DbServer)LocalDbServer).Initial("A");
				//				string id="北京";

				//在标题中显示出本机所在地
				DdbView.ActiveForm.Text+="("+id+")";

				//根据本机地址，把不能执行的查询禁止掉
				if(id=="北京")
				{
					radioLoc2.Enabled=true;
					radioRem1.Enabled=false;
					radioRem4.Enabled=false;
				}
				else if (id=="上海")
				{
					radioJoin2.Enabled=true;
					radioRem2.Enabled=false;
				}
				else
				{
					radioJoin1.Enabled=true;
					radioRem3.Enabled=false;
				}


				
			}
				///无法获得则捕捉异常，异常情况有可能是：指定的url地址不可达或者指定获得的对象定义不对
			catch( NullReferenceException nullExp )
			{
				MessageBox.Show( "The url for the object is invalid " + nullExp.Message );
			}
			catch( RemotingException remExp )
			{
				MessageBox.Show( "The object type is not defined properly, it needs to be derived for a remoting class " + remExp.Message );
			}
		
		}

		private string TypeConvert(Type myDataType)
		{
			string myOleDbType="";
			switch(myDataType.FullName)
			{
				case "System.String":
					myOleDbType="text";
					break;
				case "System.Boolean":
					myOleDbType="Bit";
					break;
				case "System.Double":
				case "System.Single":
					myOleDbType="Double";
					break;
				case "System.DateTime":
					myOleDbType="Date";
					break;
				default:
					myOleDbType="Integer";
					break;
	
			}
			return myOleDbType;
			
		}

		private void btnCreDB_Click(object sender, System.EventArgs e)
		{
	
		
		}

		private void DdbView_Load(object sender, System.EventArgs e)
		{
		
		}

		private void menuItem1_Click(object sender, System.EventArgs e)
		{
		
		}

		
	}
}