fclsdataform.cs

来自「Sams Teach Yourself C# Web Programming i」· CS 代码 · 共 313 行

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;

namespace Data_Form_Example
{
	/// <summary>
	/// Summary description for fclsDataForm.
	/// </summary>
	public class fclsDataForm : System.Windows.Forms.Form
	{
		private System.Data.OleDb.OleDbCommand oleDbSelectCommand1;
		private System.Data.OleDb.OleDbCommand oleDbInsertCommand1;
		private Data_Form_Example.AllContacts objAllContacts;
		private System.Data.OleDb.OleDbConnection oleDbConnection1;
		private System.Data.OleDb.OleDbDataAdapter oleDbDataAdapter1;
		private System.Windows.Forms.Button btnLoad;
		private System.Windows.Forms.Button btnUpdate;
		private System.Windows.Forms.Button btnCancelAll;
		private System.Windows.Forms.DataGrid grdContacts;
		/// <summary>
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.Container components = null;

		public fclsDataForm()
		{
			//
			// Required for Windows Form Designer support
			//
			InitializeComponent();

			//
			// TODO: Add any constructor code after InitializeComponent call
			//
		}

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if(components != null)
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.oleDbSelectCommand1 = new System.Data.OleDb.OleDbCommand();
			this.oleDbInsertCommand1 = new System.Data.OleDb.OleDbCommand();
			this.objAllContacts = new Data_Form_Example.AllContacts();
			this.oleDbConnection1 = new System.Data.OleDb.OleDbConnection();
			this.oleDbDataAdapter1 = new System.Data.OleDb.OleDbDataAdapter();
			this.btnLoad = new System.Windows.Forms.Button();
			this.btnUpdate = new System.Windows.Forms.Button();
			this.btnCancelAll = new System.Windows.Forms.Button();
			this.grdContacts = new System.Windows.Forms.DataGrid();
			((System.ComponentModel.ISupportInitialize)(this.objAllContacts)).BeginInit();
			((System.ComponentModel.ISupportInitialize)(this.grdContacts)).BeginInit();
			this.SuspendLayout();
			// 
			// oleDbSelectCommand1
			// 
			this.oleDbSelectCommand1.CommandText = "SELECT ContactName, State FROM Contacts";
			this.oleDbSelectCommand1.Connection = this.oleDbConnection1;
			// 
			// oleDbInsertCommand1
			// 
			this.oleDbInsertCommand1.CommandText = "INSERT INTO Contacts(ContactName, State) VALUES (?, ?)";
			this.oleDbInsertCommand1.Connection = this.oleDbConnection1;
			this.oleDbInsertCommand1.Parameters.Add(new System.Data.OleDb.OleDbParameter("ContactName", System.Data.OleDb.OleDbType.VarWChar, 255, "ContactName"));
			this.oleDbInsertCommand1.Parameters.Add(new System.Data.OleDb.OleDbParameter("State", System.Data.OleDb.OleDbType.VarWChar, 50, "State"));
			// 
			// objAllContacts
			// 
			this.objAllContacts.DataSetName = "AllContacts";
			this.objAllContacts.Locale = new System.Globalization.CultureInfo("en-US");
			this.objAllContacts.Namespace = "http://www.tempuri.org/AllContacts.xsd";
			// 
			// oleDbConnection1
			// 
			this.oleDbConnection1.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Password="""";User ID=Admin;Data Source=C:\Contacts.mdb;Mode=Share Deny None;Extended Properties="""";Jet OLEDB:System database="""";Jet OLEDB:Registry Path="""";Jet OLEDB:Database Password="""";Jet OLEDB:Engine Type=5;Jet OLEDB:Database Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global Bulk Transactions=1;Jet OLEDB:New Database Password="""";Jet OLEDB:Create System Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDB:Don't Copy Locale on Compact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False";
			// 
			// oleDbDataAdapter1
			// 
			this.oleDbDataAdapter1.InsertCommand = this.oleDbInsertCommand1;
			this.oleDbDataAdapter1.SelectCommand = this.oleDbSelectCommand1;
			this.oleDbDataAdapter1.TableMappings.AddRange(new System.Data.Common.DataTableMapping[] {
																										new System.Data.Common.DataTableMapping("Table", "Contacts", new System.Data.Common.DataColumnMapping[] {
																																																					new System.Data.Common.DataColumnMapping("ContactName", "ContactName"),
																																																					new System.Data.Common.DataColumnMapping("State", "State")})});
			// 
			// btnLoad
			// 
			this.btnLoad.Location = new System.Drawing.Point(10, 10);
			this.btnLoad.Name = "btnLoad";
			this.btnLoad.TabIndex = 0;
			this.btnLoad.Text = "&Load";
			this.btnLoad.Click += new System.EventHandler(this.btnLoad_Click);
			// 
			// btnUpdate
			// 
			this.btnUpdate.Location = new System.Drawing.Point(315, 10);
			this.btnUpdate.Name = "btnUpdate";
			this.btnUpdate.TabIndex = 1;
			this.btnUpdate.Text = "&Update";
			this.btnUpdate.Click += new System.EventHandler(this.btnUpdate_Click);
			// 
			// btnCancelAll
			// 
			this.btnCancelAll.Location = new System.Drawing.Point(315, 43);
			this.btnCancelAll.Name = "btnCancelAll";
			this.btnCancelAll.TabIndex = 2;
			this.btnCancelAll.Text = "Ca&ncel All";
			this.btnCancelAll.Click += new System.EventHandler(this.btnCancelAll_Click);
			// 
			// grdContacts
			// 
			this.grdContacts.DataMember = "Contacts";
			this.grdContacts.DataSource = this.objAllContacts;
			this.grdContacts.HeaderForeColor = System.Drawing.SystemColors.ControlText;
			this.grdContacts.Location = new System.Drawing.Point(10, 76);
			this.grdContacts.Name = "grdContacts";
			this.grdContacts.Size = new System.Drawing.Size(380, 164);
			this.grdContacts.TabIndex = 3;
			// 
			// fclsDataForm
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
			this.ClientSize = new System.Drawing.Size(392, 223);
			this.Controls.AddRange(new System.Windows.Forms.Control[] {
																		  this.btnLoad,
																		  this.btnUpdate,
																		  this.btnCancelAll,
																		  this.grdContacts});
			this.Name = "fclsDataForm";
			this.Text = "fclsDataForm";
			((System.ComponentModel.ISupportInitialize)(this.objAllContacts)).EndInit();
			((System.ComponentModel.ISupportInitialize)(this.grdContacts)).EndInit();
			this.ResumeLayout(false);

		}
		#endregion

		public void FillDataSet(Data_Form_Example.AllContacts dataSet)
		{
			// Turn off constraint checking before the dataset is filled.
			// This allows the adapters to fill the dataset without concern
			// for dependencies between the tables.
			dataSet.EnforceConstraints = false;
			try 
			{
				// Open the connection.
				this.oleDbConnection1.Open();
				// Attempt to fill the dataset through the OleDbDataAdapter1.
				this.oleDbDataAdapter1.Fill(dataSet);
			}
			catch (System.Exception fillException) 
			{
				// Add your error handling code here.
				throw fillException;
			}
			finally 
			{
				// Turn constraint checking back on.
				dataSet.EnforceConstraints = true;
				// Close the connection whether or not the exception was thrown.
				this.oleDbConnection1.Close();
			}

		}

		public void UpdateDataSource(Data_Form_Example.AllContacts ChangedRows)
		{
			try 
			{
				// The data source only needs to be updated if there are changes pending.
				if ((ChangedRows != null)) 
				{
					// Open the connection.
					this.oleDbConnection1.Open();
					// Attempt to update the data source.
					oleDbDataAdapter1.Update(ChangedRows);
				}
			}
			catch (System.Exception updateException) 
			{
				// Add your error handling code here.
				throw updateException;
			}
			finally 
			{
				// Close the connection whether or not the exception was thrown.
				this.oleDbConnection1.Close();
			}

		}

		public void LoadDataSet()
		{
			// Create a new dataset to hold the records returned from the call to FillDataSet.
			// A temporary dataset is used because filling the existing dataset would
			// require the databindings to be rebound.
			Data_Form_Example.AllContacts objDataSetTemp;
			objDataSetTemp = new Data_Form_Example.AllContacts();
			try 
			{
				// Attempt to fill the temporary dataset.
				this.FillDataSet(objDataSetTemp);
			}
			catch (System.Exception eFillDataSet) 
			{
				// Add your error handling code here.
				throw eFillDataSet;
			}
			try 
			{
				// Empty the old records from the dataset.
				objAllContacts.Clear();
				// Merge the records into the main dataset.
				objAllContacts.Merge(objDataSetTemp);
			}
			catch (System.Exception eLoadMerge) 
			{
				// Add your error handling code here.
				throw eLoadMerge;
			}

		}

		public void UpdateDataSet()
		{
			// Create a new dataset to hold the changes that have been made to the main dataset.
			Data_Form_Example.AllContacts objDataSetChanges = new Data_Form_Example.AllContacts();
			// Stop any current edits.
			this.BindingContext[objAllContacts,"Contacts"].EndCurrentEdit();
			// Get the changes that have been made to the main dataset.
			objDataSetChanges = ((Data_Form_Example.AllContacts)(objAllContacts.GetChanges()));
			// Check to see if any changes have been made.
			if ((objDataSetChanges != null)) 
			{
				try 
				{
					// There are changes that need to be made, so attempt to update the datasource by
					// calling the update method and passing the dataset and any parameters.
					this.UpdateDataSource(objDataSetChanges);
					objAllContacts.Merge(objDataSetChanges);
					objAllContacts.AcceptChanges();
				}
				catch (System.Exception eUpdate) 
				{
					// Add your error handling code here.
					throw eUpdate;
				}
				// Add your code to check the returned dataset for any errors that may have been
				// pushed into the row object's error.
			}

		}

		private void btnCancelAll_Click(object sender, System.EventArgs e)
		{
			this.objAllContacts.RejectChanges();

		}

		private void btnLoad_Click(object sender, System.EventArgs e)
		{
			try 
			{
				// Attempt to load the dataset.
				this.LoadDataSet();
			}
			catch (System.Exception eLoad) 
			{
				// Add your error handling code here.
				// Display error message, if any.
				System.Windows.Forms.MessageBox.Show(eLoad.Message);
			}

		}

		private void btnUpdate_Click(object sender, System.EventArgs e)
		{
			try 
			{
				// Attempt to update the datasource.
				this.UpdateDataSet();
			}
			catch (System.Exception eUpdate) 
			{
				// Add your error handling code here.
				// Display error message, if any.
				System.Windows.Forms.MessageBox.Show(eUpdate.Message);
			}

		}
	}
}