mainform.cs

这是用C#数据库编程的实例

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

namespace databrowser
{
	/// <summary>
	/// MainForm 的摘要说明。
	/// </summary>
	public class MainForm : System.Windows.Forms.Form
	{
		private System.Windows.Forms.MainMenu mainMenu1;
		private System.Windows.Forms.MenuItem menuItem1;
		private System.Windows.Forms.MenuItem menuItem2;
		private System.Windows.Forms.MenuItem menuItem3;
		private System.Windows.Forms.MenuItem menuItem4;
		private System.Windows.Forms.MenuItem menuItem5;
		private System.Windows.Forms.MenuItem menuItem7;
		/// <summary>
		/// 必需的设计器变量。
		/// </summary>
		private System.ComponentModel.Container components = null;
		private String ConnectionStringAccess="";
		private String ConnectionString="";
		public MainForm()
		{
			//
			// Windows 窗体设计器支持所必需的
			//
			InitializeComponent();
			MenuItem miWindow = mainMenu1.MenuItems.Add("窗口(&w)");
			//增加菜单项
			miWindow.MergeOrder = 10;
			//设置菜单项
			miWindow.MdiList = true;
		}

		/// <summary>
		/// 清理所有正在使用的资源。
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if(components != null)
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{
			this.mainMenu1 = new System.Windows.Forms.MainMenu();
			this.menuItem1 = new System.Windows.Forms.MenuItem();
			this.menuItem2 = new System.Windows.Forms.MenuItem();
			this.menuItem3 = new System.Windows.Forms.MenuItem();
			this.menuItem4 = new System.Windows.Forms.MenuItem();
			this.menuItem5 = new System.Windows.Forms.MenuItem();
			this.menuItem7 = new System.Windows.Forms.MenuItem();
			// 
			// mainMenu1
			// 
			this.mainMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.menuItem1,
																					  this.menuItem5});
			// 
			// menuItem1
			// 
			this.menuItem1.Index = 0;
			this.menuItem1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.menuItem2,
																					  this.menuItem3,
																					  this.menuItem4});
			this.menuItem1.Text = "文件（&F）";
			// 
			// menuItem2
			// 
			this.menuItem2.Index = 0;
			this.menuItem2.Text = "登陆ACCESS";
			this.menuItem2.Click += new System.EventHandler(this.menuItem2_Click);
			// 
			// menuItem3
			// 
			this.menuItem3.Enabled = false;
			this.menuItem3.Index = 1;
			this.menuItem3.Text = "登陆SQL";
			this.menuItem3.Click += new System.EventHandler(this.menuItem3_Click);
			// 
			// menuItem4
			// 
			this.menuItem4.Index = 2;
			this.menuItem4.Text = "退出（&E）";
			// 
			// menuItem5
			// 
			this.menuItem5.Index = 1;
			this.menuItem5.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
																					  this.menuItem7});
			this.menuItem5.Text = "工具（&T）";
			// 
			// menuItem7
			// 
			this.menuItem7.Index = 0;
			this.menuItem7.Text = "查询分析器（&A）";
			this.menuItem7.Click += new System.EventHandler(this.menuItem7_Click);
			// 
			// MainForm
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
			this.ClientSize = new System.Drawing.Size(512, 305);
			this.IsMdiContainer = true;
			this.Menu = this.mainMenu1;
			this.Name = "MainForm";
			this.Text = "MainForm";

		}
		#endregion

		private void menuItem2_Click(object sender, System.EventArgs e)
		{
			LoginAccess();
			//登录access
		}
		private void Login()
		{
			//登录Access函数
			String userName="";
			//存储用户名
			String password ="";
			//存储密码
			String database ="";
			//存储数据源
			String SQLServer="";
			//存储服务器
			login SQLlogin=new login(ref userName
				,ref password,ref database,ref SQLServer,this);
			//创建登录窗体，并取得登录数据
			if(userName.Length != 0 && 
				database.Length != 0 && SQLServer.Length != 0)
			{
				//如果存在用户名和服务器
				menuItem3.Enabled = false;
				//使menuItem3不可用
				frmDatabaseExplorer frmExplore=new frmDatabaseExplorer(ref userName
					,ref password,ref database,ref SQLServer);
				//创建数据库查看器
				if(frmExplore.buildTreeView())
				{
					//如果查看器成功的建立了树目录
					menuItem5.Enabled = true;
					//使menuItem5可用
					menuItem3.Enabled = false;
					//使MenuItem3不可以用
					frmExplore.MdiParent= this;
					//取得父窗体
					frmExplore.WindowState = FormWindowState.Maximized;
					//最大化
					frmExplore.Show();
					//显示父窗体
					ConnectionString = frmExplore.ConnectionString;
					//取得链接路径
				}//if
				else
				{
					menuItem3.Enabled = true;
					//使menuItem3可用
				}//if
			}//if
		}
		private void LoginAccess()
		{
			//登录Access函数
			String userName="";
			//存储用户名
			String password ="";
			//存储密码
			String database ="";
			//存储数据源
			String SQLServer="";
			//存储服务器
			LoginAccess access  = new LoginAccess(ref userName
				,ref password,ref database,ref SQLServer,this) ;
			//通过LoginAccess类构造一个新窗体并取得数据库参量
			if(userName.Length != 0 && database.Length != 0 
				&& SQLServer.Length != 0)
			{
				//如果用户名和数据库路径存在
				menuItem2.Enabled = true;
				//将菜单项menuItem2设为可用
				AccessExplorer frmExplore = new AccessExplorer(ref userName
					,ref password,ref database,ref SQLServer);
				//调用AccessExplorer类建立新窗体并传递数据库参量
				if(frmExplore.buildTreeView())
				{
					//创建树目录成功
					menuItem5.Enabled = true;
					//将菜单项menuItem5设为可用
					menuItem2.Enabled = false;
					//将菜单项menuItem2设为可用
					frmExplore.MdiParent = this;
					//取得父窗体
					frmExplore.WindowState = FormWindowState.Maximized;
					//最大化
					frmExplore.Show();
					//显示窗体
					ConnectionStringAccess = frmExplore.ConnectionString;
					//取得链接路径
				}
				else
				{
					menuItem2.Enabled = true;
					//使menuItem2可用
				}//if			
			}//if
		}
		/// <summary>
		/// 应用程序的主入口点。
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new MainForm());
		}

		private void menuItem7_Click(object sender, System.EventArgs e)
		{
			QueryAnalyzer myquery=new QueryAnalyzer(ref ConnectionStringAccess);			
			myquery.MdiParent=this;
			myquery.Show();
			
		}

		private void menuItem3_Click(object sender, System.EventArgs e)
		{
		
		}
	}
}