| 插入資料記錄: 和前面二種操作在思路是一致的,就是通過ADO.NET首先插入資料記錄到資料庫,然後對"DataSet"對象進行必要的修改。下列代碼就是以Access 2000資料庫為模型插入一條資料記錄的代碼 protected void Insert_record ( object sender , System.EventArgs e ) { try { file://判斷所有欄位是否添完,添完則執行,反之彈出提示 if ( t_id.Text != "" && t_xm.Text != "" && t_xb.Text != "" && t_nl.Text != "" && t_books.Text != "" ) { string myConn1 = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb" ; OleDbConnection myConn = new OleDbConnection ( myConn1 ) ; myConn.Open ( ) ; string strInsert = " INSERT INTO person ( id , xm , xb , nl , zip ) VALUES ( " ; strInsert += t_id.Text + ", '" ; strInsert += t_xm.Text + "', '" ; strInsert += t_xb.Text + "', " ; strInsert += t_nl.Text + ", " ; strInsert += t_books.Text + ")" ; OleDbCommand inst = new OleDbCommand ( strInsert , myConn ) ; inst.ExecuteNonQuery ( ) ; myConn.Close ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . BeginEdit ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . EndEdit ( ) ; myDataSet.Tables [ "person" ] . AcceptChanges ( ) ; } else { MessageBox.Show ( "必須填滿所有欄位值!" , "錯誤!" ) ; } } catch ( Exception ed ) { MessageBox.Show ( "儲存資料記錄發生 " + ed.ToString ( ) , "錯誤!" ) ; } } 同樣對Sql Server 2000資料庫進行插入記錄操作和Access 2000資料庫插入記錄操作的差異也只在於不同的資料連結,具體的代碼可以參考"刪除資料記錄"中的代碼,在這裡就不提供了。 六.Visual C#資料庫編程的完成原始碼和程式啟動並執行主介面: 掌握了上面要點,編寫一個完整的資料庫編程的程式就顯得非常容易了,下面是Visual C#進行資料庫編程的完整代碼(Data01.cs),此代碼是以Access 2000資料庫為模型設計的,具體如下: using System ; using System.Drawing ; using System.ComponentModel ; using System.Windows.Forms ; using System.Data.OleDb ; using System.Data ; public class Data : Form { private System.ComponentModel.Container components = null ; private Button lastrec ; private Button nextrec ; private Button previousrec ; private Button firstrec ; private TextBox t_books ; private TextBox t_nl ; private ComboBox t_xb ; private TextBox t_xm ; private TextBox t_id ; private Label l_books ; private Label l_nl ; private Label l_xb ; private Label l_xm ; private Label l_id ; private Label label1 ; private DataSet myDataSet ; private Button button1 ; private Button button2 ; private Button button3 ; private Button button4 ; private BindingManagerBase myBind ; public Data ( ) { file://串連到一個資料庫 GetConnected ( ) ; // 對表單中所需要的內容進行初始化 InitializeComponent ( ) ; } file://清除在程式中使用過的資源 protected override void Dispose( bool disposing ) { if( disposing ) { if ( components != null ) { components.Dispose ( ) ; } } base.Dispose( disposing ) ; } public static void Main ( ) { Application.Run ( new Data ( ) ) ; } public void GetConnected ( ) { try { file://建立一個 OleDbConnection string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb" ; OleDbConnection myConn = new OleDbConnection ( strCon ) ; string strCom = " SELECT * FROM person " ; file://建立一個 DataSet myDataSet = new DataSet ( ) ; myConn.Open ( ) ; file://用 OleDbDataAdapter 得到一個資料集 OleDbDataAdapter myCommand = new OleDbDataAdapter ( strCom , myConn ) ; file://把Dataset綁定books資料表 myCommand.Fill ( myDataSet , "person" ) ; file://關閉此OleDbConnection myConn.Close ( ) ; } catch ( Exception e ) { MessageBox.Show ( "串連錯誤! " + e.ToString ( ) , "錯誤" ) ; } } private void InitializeComponent ( ) { file://添加控制項,略 this.Name = "Data" ; this.Text = "Visual C#的資料庫編程!" ; this.ResumeLayout(false) ; myBind = this.BindingContext [ myDataSet , "person" ] ; } protected void New_record ( object sender , System.EventArgs e ) { t_id.Text = ( myBind.Count + 1 ).ToString ( ) ; t_xm.Text = "" ; t_xb.Text = "" ; t_nl.Text = "" ; t_books.Text = "" ; } protected void Insert_record ( object sender , System.EventArgs e ) { try { file://判斷所有欄位是否添完,添完則執行,反之彈出提示 if ( t_id.Text != "" && t_xm.Text != "" && t_xb.Text != "" && t_nl.Text != "" && t_books.Text != "" ) { string myConn1 = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb" ; OleDbConnection myConn = new OleDbConnection ( myConn1 ) ; myConn.Open ( ) ; string strInsert = " INSERT INTO person ( id , xm , xb , nl , zip ) VALUES ( " ; strInsert += t_id.Text + ", '" ; strInsert += t_xm.Text + "', '" ; strInsert += t_xb.Text + "', " ; strInsert += t_nl.Text + ", " ; strInsert += t_books.Text + ")" ; OleDbCommand inst = new OleDbCommand ( strInsert , myConn ) ; inst.ExecuteNonQuery ( ) ; myConn.Close ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . BeginEdit ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . EndEdit ( ) ; myDataSet.Tables [ "person" ] . AcceptChanges ( ) ; } else { MessageBox.Show ( "必須填滿所有欄位值!" , "錯誤!" ) ; } } catch ( Exception ed ) { MessageBox.Show ( "儲存資料記錄發生 " + ed.ToString ( ) , "錯誤!" ) ; } } protected void Update_record ( object sender , System.EventArgs e ) { int i = myBind.Position ; try{ file://串連到一個資料庫 string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb " ; OleDbConnection myConn = new OleDbConnection ( strCon ) ; myConn.Open ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . BeginEdit ( ) ; file://從資料庫中修改指定記錄 string strUpdt = " UPDATE person SET xm = '" + t_xm.Text + "' , xb = '" + t_xb.Text + "' , nl = " + t_nl.Text + " , zip = " + t_books.Text + " WHERE id = " + t_id.Text ; OleDbCommand myCommand = new OleDbCommand ( strUpdt , myConn ) ; myCommand.ExecuteNonQuery ( ) ; myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . EndEdit ( ) ; myDataSet.Tables [ "person" ] . AcceptChanges ( ) ; myConn.Close ( ) ; } catch ( Exception ed ) { MessageBox.Show ( "修改指定記錄錯誤: " + ed.ToString ( ) , "錯誤!" ) ; } myBind.Position = i ; } protected void Delete_record ( object sender , System.EventArgs e ) { DialogResult r = MessageBox.Show ( "是否刪除目前記錄!" , "刪除目前記錄!" , MessageBoxButtons.YesNo , MessageBoxIcon.Question ) ; int ss = ( int ) r ; if ( ss == 6 ) // 按動"確定"按鈕 { try{ file://串連到一個資料庫 string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb " ; OleDbConnection myConn = new OleDbConnection ( strCon ) ; myConn.Open ( ) ; string strDele = "DELETE FROM person WHERE id= " + t_id.Text ; OleDbCommand myCommand = new OleDbCommand ( strDele , myConn ) ; file://從資料庫中刪除指定記錄 myCommand.ExecuteNonQuery ( ) ; file://從DataSet中刪除指定記錄 myDataSet.Tables [ "person" ] . Rows [ myBind.Position ] . Delete ( ) ; myDataSet.Tables [ "person" ] . AcceptChanges ( ) ; myConn.Close ( ) ; } catch ( Exception ed ) { MessageBox.Show ( "刪除記錄錯誤資訊: " + ed.ToString ( ) , "錯誤!" ) ; } } } file://按鈕"尾記錄"對象事件程式 protected void GoLast ( object sender , System.EventArgs e ) { myBind.Position = myBind.Count - 1 ; } file://按鈕"下一條"對象事件程式 protected void GoNext ( object sender , System.EventArgs e ) { if ( myBind.Position == myBind.Count -1 ) MessageBox.Show ( "已經到了最後一條記錄!", "資訊提示!" , MessageBoxButtons.OK , MessageBoxIcon.Information ) ; else myBind.Position += 1 ; } file://按鈕"上一條"對象事件程式 protected void GoPrevious ( object sender , System.EventArgs e ) { if ( myBind.Position == 0 ) MessageBox.Show ( "已經到了第一條記錄!" , "資訊提示!" , MessageBoxButtons.OK , MessageBoxIcon.Information ) ; else myBind.Position -= 1 ; } file://按鈕"首記錄"對象事件程式 protected void GoFirst ( object sender , System.EventArgs e ) { myBind.Position = 0 ; } } 對於以Sql Server 2000資料庫為模型的程式碼,只要把Data01.cs中的資料連結,即: string myConn1 = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = db.mdb" ; 改換成: string strCon = "Provider = SQLOLEDB.1 ; Persist Security Info = False ; User ID = sa ; Initial Catalog = data1 ; Data Source = server1 " ; 注釋:此資料連結代表的意思是:開啟Sql server資料庫,伺服器名稱為server1,資料庫為data1 就可以得到Visual C#針對Sql Server 2000資料庫為模板編程的完成來源程式代碼了。所以本文就不再提供了。 七.總結: 資料庫編程始終是程式編程內容中的一個重點和痛點。而以上介紹的這些操作又是資料庫編程中最為基本,也是最為重要的內容。那些複雜的編程無非是以上這些處理的若干個疊加。 |