用Visual C＃来增加数据记录(1)

在本篇文章中，我们将介绍Visual C#对数据库的一个基本操作，即：如何往数据库中添加记录。我们将通过一些数据库操作的例子，来具体说明一下。为了更清楚的说明这个问题，在选用数据库方面采用了二种当前比较典型的数据库，其一是本地数据库--Access 2000，另外一个是远程数据库--SQL SERVER 7.0。首先介绍如何用Visual C#来添加Access 2000数据库的记录。

一．用Visual C#来添加Access 2000数据库的记录
（一）.程序设计和运行的环境设置：
（1）视窗2000服务器版
（2）Microsoft Data Acess Component 2.6 以上版本 ( MDAC 2.6 )
（3）本文程序使用的数据库的介绍：

程序中使用的数据库名称为sample.mdb，在此数据库中有一张数据表books。此数据表的结构如下：
字段名称 字段类型 代表意思
Bookid 数字 序号
booktitle 文本 书籍名称
bookauthor 文本 书籍作者
bookprice 数字 价格
bookstock 数字 书架号

（二）.程序设计难点和应该注意的问题：
如何正确的往数据库中添加记录是本文要讨论的一个重点和难点，下面就是解决这一问题的具体思路：
（1）创建并打开一个 OleDbConnection对象。
（2）创建一个插入一条记录的SQL语句。
（3）创建一个OleDbCommand对象。
（4）通过此OleDbCommand对象完成对插入一条记录到数据库的操作。
以下是在程序中实现的具体语句：
string strConn = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = sample.mdb " ;
OleDbConnection myConn = new OleDbConnection ( strConn ) ;
myConn.Open ( ) ;
string strInsert = " INSERT INTO books ( bookid , booktitle , bookauthor , bookprice , bookstock ) VALUES ( " ;
strInsert += t_bookid.Text + ", '" ;
strInsert += t_booktitle.Text + "', '" ;
strInsert += t_bookauthor.Text + "', " ;
strInsert += t_bookprice.Text + ", " ;
strInsert += t_bookstock.Text + ")" ;
OleDbCommand inst = new OleDbCommand ( strInsert , myConn ) ;
inst.ExecuteNonQuery ( ) ;
myConn.Close ( ) ;

（三）.用Visual C#来插入记录的程序源代码( add.cs )和执行后的界面：
下图是add.cs编译后的执行界面：

add.cs源程序代码：
using System ;
using System.Drawing ;
using System.ComponentModel ;
using System.Windows.Forms ;
using System.Data.OleDb ;
using System.Data ;
//导入程序中使用到的名称空间
public class DataAdd : Form {
private Button lastrec ;
private Button nextrec ;
private Button previousrec ;
private Button firstrec ;
private Container components ;
private Label title ;
private Button t_new ;
private Button save ;
private TextBox t_bookstock ;
private TextBox t_bookprice ;
private TextBox t_bookauthor ;
private TextBox t_booktitle ;
private TextBox t_bookid ;
private Label l_bookstock ;
private Label l_bookprice ;
private Label l_bookauthor ;
private Label l_booktitle ;
private Label l_bookid ;
private DataSet myDataSet ;
private BindingManagerBase myBind ;
//定义在程序中要使用的组件
public DataAdd ( ) {
//连接到一个数据库
GetConnected ( ) ;
// 对窗体中所需要的内容进行初始化
InitializeComponent ( );
}
//释放程序使用过的所以资源
public override void Dispose ( ) {
base.Dispose ( ) ;
components.Dispose ( ) ;
}
public static void Main ( ) {
Application.Run ( new DataAdd ( ) ) ;
}
public void GetConnected ( )
{
try{
//创建一个 OleDbConnection对象
string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = sample.mdb" ;
OleDbConnection myConn = new OleDbConnection ( strCon ) ;
string strCom = " SELECT * FROM books " ;
//创建一个 DataSet
myDataSet = new DataSet ( ) ;
myConn.Open ( ) ;
//用 OleDbDataAdapter 得到一个数据集
OleDbDataAdapter myCommand = new OleDbDataAdapter ( strCom , myConn ) ;
//把Dataset绑定books数据表
myCommand.Fill ( myDataSet , "books" ) ;
//关闭此OleDbConnection
myConn.Close ( ) ;
}
catch ( Exception e )
{
MessageBox.Show ( "连接错误! " + e.ToString ( ) , "错误" ) ;
}
}
private void InitializeComponent ( )
{
components = new System.ComponentModel.Container ( ) ;
nextrec = new Button ( ) ;
lastrec = new Button ( ) ;
previousrec = new Button ( ) ;
firstrec = new Button ( ) ;
t_bookprice = new TextBox ( ) ;
l_booktitle = new Label ( ) ;
l_bookprice = new Label ( ) ;
l_bookauthor = new Label ( ) ;
t_bookid = new TextBox ( ) ;
save = new Button ( ) ;
title = new Label ( ) ;
t_bookauthor = new TextBox ( ) ;
t_booktitle = new TextBox ( ) ;
t_new = new Button ( ) ;
l_bookstock = new Label ( ) ;
t_bookstock = new TextBox ( ) ;
l_bookid = new Label ( ) ;
//以下是对数据浏览的四个按钮进行初始化
firstrec.Location = new System.Drawing.Point ( 65 , 312 ) ;
firstrec.ForeColor = System.Drawing.Color.Black ;
firstrec.Size = new System.Drawing.Size ( 40 , 24 ) ;
firstrec.Font = new System.Drawing.Font("仿宋", 8f );
firstrec.Text = "首记录";
firstrec.Click += new System.EventHandler(GoFirst);
previousrec.Location = new System.Drawing.Point ( 135 , 312 ) ;
previousrec.ForeColor = System.Drawing.Color.Black ;
previousrec.Size = new System.Drawing.Size(40, 24) ;
previousrec.Font = new System.Drawing.Font ( "仿宋" , 8f ) ;
previousrec.Text = "上一条" ;
previousrec.Click += new System.EventHandler ( GoPrevious ) ;
nextrec.Location = new System.Drawing.Point ( 205 , 312 );
nextrec.ForeColor = System.Drawing.Color.Black ;
nextrec.Size = new System.Drawing.Size ( 40 , 24 ) ;
nextrec.Font = new System.Drawing.Font ( "仿宋" , 8f ) ;
nextrec.Text = "下一条" ;
nextrec.Click += new System.EventHandler ( GoNext );
lastrec.Location = new System.Drawing.Point ( 275 , 312 ) ;
lastrec.ForeColor = System.Drawing.Color.Black ;
lastrec.Size = new System.Drawing.Size ( 40 , 24 ) ;
lastrec.Font = new System.Drawing.Font ( "仿宋" , 8f ) ;
lastrec.Text = "尾记录" ;
lastrec.Click += new System.EventHandler ( GoLast ) ;
//以下是对显示标签进行初始化
l_bookid.Location = new System.Drawing.Point ( 24 , 56 ) ;
l_bookid.Text = "书本序号：" ;
l_bookid.Size = new System.Drawing.Size ( 112, 20 ) ;
l_bookid.Font = new System.Drawing.Font ( "仿宋" , 10f ) ;
l_bookid.TextAlign = System.Drawing.ContentAlignment.MiddleCenter ;
l_booktitle.Location = new System.Drawing.Point ( 24 , 108 ) ;
l_booktitle.Text = "书 名：";
l_booktitle.Size = new System.Drawing.Size ( 112 , 20 ) ;
l_booktitle.Font = new System.Drawing.Font ( "仿宋" , 10f ) ;
l_booktitle.TextAlign = System.Drawing.ContentAlignment.MiddleCenter ;
l_bookprice.Location = new System.Drawing.Point ( 24 , 212 ) ;
l_bookprice.Text = "价 格：" ;
l_bookprice.Size = new System.Drawing.Size ( 112 , 20 ) ;
l_bookprice.Font = new System.Drawing.Font ( "仿宋" , 10f ) ;
l_bookprice.TextAlign = System.Drawing.ContentAlignment.MiddleCenter ;
l_bookstock.Location = new System.Drawing.Point ( 24 , 264 ) ;
l_bookstock.Text = "书 架 号：" ;
l_bookstock.Size = new System.Drawing.Size ( 112 , 20 ) ;
l_bookstock.Font = new System.Drawing.Font ( "仿宋" , 10f ) ;
l_bookstock.TabIndex = 16 ;
l_bookstock.TextAlign = System.Drawing.ContentAlignment.MiddleCenter ;
l_bookauthor.Location = new System.Drawing.Point ( 24 , 160 ) ;
l_bookauthor.Text = "作 者：" ;
l_bookauthor.Size = new System.Drawing.Size ( 112 , 20 ) ;
l_bookauthor.Font = new System.Drawing.Font ( "仿宋" , 10f ) ;
l_bookauthor.TextAlign = System.Drawing.ContentAlignment.MiddleCenter ;
title.Location = new System.Drawing.Point ( 32 , 16 ) ;
title.Text = "利用Vsiual C#来增加数据记录！" ;
title.Size = new System.Drawing.Size ( 336 , 24 ) ;
title.ForeColor = System.Drawing.Color.Green ;
title.Font = new System.Drawing.Font ( "仿宋" , 14f , System.Drawing.FontStyle.Bold ) ;
//以下是对为显示数据记录而设定的标签和文本框进行初始化，并把记录绑定在不同的绑定到文本框"Text"属性上
t_bookid.Location = new System.Drawing.Point ( 184 , 56 ) ;
t_bookid.Size = new System.Drawing.Size ( 80 , 20 ) ;
t_bookid.DataBindings.Add ( "Text" , myDataSet , "books.bookid" ) ;
t_bookstock.Location = new System.Drawing.Point ( 184 , 264 ) ;
t_bookstock.Size = new System.Drawing.Size ( 80 , 20 ) ;
t_bookstock.DataBindings.Add ( "Text" , myDataSet , "books.bookstock" ) ;
t_booktitle.Location = new System.Drawing.Point ( 184 , 108 ) ;
t_booktitle.Size = new System.Drawing.Size ( 176 , 20 ) ;
t_booktitle.DataBindings.Add( "Text" , myDataSet , "books.booktitle" ) ;
t_bookprice.Location = new System.Drawing.Point ( 184 , 212 ) ;
t_bookprice.Size = new System.Drawing.Size ( 80 , 20 ) ;
t_bookprice.DataBindings.Add ( "Text" , myDataSet , "books.bookprice" ) ;
t_bookauthor.Location = new System.Drawing.Point ( 184 , 160 ) ;
t_bookauthor.Size = new System.Drawing.Size ( 128 , 20 ) ;
t_bookauthor.DataBindings.Add ( "Text" , myDataSet , "books.bookauthor" ) ;
t_new.Location = new System.Drawing.Point ( 62 , 354 ) ;
t_new.Size = new System.Drawing.Size ( 96 , 32 ) ;
t_new.Text = "新建记录" ;
t_new.Click += new System.EventHandler ( t_newClick ) ;
save.Location = new System.Drawing.Point ( 222 , 354 ) ;
save.Size = new System.Drawing.Size ( 96 , 32 ) ;
save.TabIndex = 4 ;
save.Text = "保存记录" ;
save.Click += new System.EventHandler ( saveClick ) ;
this.Text = "利用Vsiual C#来增加数据记录的程序窗口！" ;
this.AutoScaleBaseSize = new System.Drawing.Size ( 5 , 13 ) ;
this.FormBorderStyle = FormBorderStyle.Fixed3D ;
this.ClientSize = new System.Drawing.Size ( 390 , 400 ) ;
//在窗体中加入下列组件
this.Controls.Add ( lastrec ) ;
this.Controls.Add ( nextrec ) ;
this.Controls.Add ( previousrec ) ;
this.Controls.Add ( firstrec ) ;
this.Controls.Add ( title ) ;
this.Controls.Add ( t_new ) ;
this.Controls.Add ( save ) ;
this.Controls.Add ( t_bookstock ) ;
this.Controls.Add ( t_bookprice ) ;
this.Controls.Add ( t_bookauthor ) ;
this.Controls.Add ( t_booktitle ) ;
this.Controls.Add ( t_bookid ) ;
this.Controls.Add ( l_bookstock ) ;
this.Controls.Add ( l_bookprice ) ;
this.Controls.Add ( l_bookauthor ) ;
this.Controls.Add ( l_booktitle ) ;
this.Controls.Add ( l_bookid ) ;
//把对象DataSet和"books"数据表绑定到此myBind对象
myBind= this.BindingContext [ myDataSet , "books" ] ;
}
protected void saveClick ( object sender , System.EventArgs e )
{
try
{
//判断所有字段是否添完，添完则执行，反之弹出提示
if ( t_bookid.Text != "" && t_booktitle.Text != "" && t_bookauthor.Text != "" && t_bookprice.Text != "" && t_bookstock.Text != "" )
{
string strConn = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = sample.mdb " ;
OleDbConnection myConn = new OleDbConnection ( strConn ) ;
myConn.Open ( ) ;
string strInsert = " INSERT INTO books ( bookid , booktitle , bookauthor , bookprice , bookstock ) VALUES ( " ;
strInsert += t_bookid.Text + ", '" ;
strInsert += t_booktitle.Text + "', '" ;
strInsert += t_bookauthor.Text + "', " ;
strInsert += t_bookprice.Text + ", " ;
strInsert += t_bookstock.Text + ")" ;
OleDbCommand inst = new OleDbCommand ( strInsert , myConn ) ;
inst.ExecuteNonQuery ( ) ;
myConn.Close ( ) ;
}
else
{
MessageBox.Show ( "必须填满所有字段值！" , "错误！" ) ;
}
}
catch ( Exception ed )
{
MessageBox.Show ( "保存数据记录发生 " + ed.ToString ( ) , "错误！" ) ;
}
}
protected void t_newClick ( object sender , System.EventArgs e )
{
t_bookid.Text = "" ;
t_booktitle.Text = "" ;
t_bookauthor.Text = "" ;
t_bookprice.Text = "" ;
t_bookstock.Text = "" ;
}
//按钮"尾记录"对象事件程序
protected void GoLast ( object sender , System.EventArgs e )
{
myBind.Position = myBind.Count - 1 ;
}

//按钮"下一条"对象事件程序
protected void GoNext ( object sender , System.EventArgs e )
{
if ( myBind.Position == myBind.Count -1 )
MessageBox.Show ( "已经到了最后一条记录！" ) ;
else
myBind.Position += 1 ;
}
//按钮"上一条"对象事件程序
protected void GoPrevious ( object sender , System.EventArgs e )
{
if ( myBind.Position == 0 )
MessageBox.Show ( "已经到了第一条记录！" ) ;
else
myBind.Position -= 1 ;
}
//按钮"首记录"对象事件程序
protected void GoFirst ( object sender , System.EventArgs e )
{
myBind.Position = 0 ;
}
}

成功编译上面代码，就可以往Access 2000数据库里面插入记录了。