vb.net还原数据库,vbios还原

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vb.net 怎么操作数据库

如果楼主熟悉VB6，可以直接在项目中添加ADODB的Com引用，这样你就可以像VB6那样操作数据库了！

另外

.NET Framework中连接数据库要用到ADO.NET。如果要操作Access数据库，要用到System.Data.OleDb命名空间下的许多类。

比如按楼主所说，“我想在textbox1中显示表一中【一些数据】字段下的第一个内容”：

'首先导入命名空间

Imports System.Data

Imports System.Data.OleDb

'然后在某一个事件处理程序中写：

Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=数据库.accdb;Jet OLEDB:Database Password=MyDbPassword")

Dim command As New OleDbCommand("Select * From 数据表", conn)

conn.Open() '打开数据库连接

Dim reader As OleDbDataReader = command.ExecuteReader() '执行SQL语句，返回OleDbDataReader 对象

Do While reader.Read() '读取一条数据

textbox1.Text += reader("一些数据") VbCrLf

Loop

reader.Close() '关闭OleDbDataReader

conn.Close() '关闭连接

相关问答

Q1: VB.NET 怎么调用备份恢复SQL2008 数据库？求源码。。

引用Microsoft SQLDMO Object Library

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

Dim SQLSER As New SQLDMO.SQLServer

SQLSER.Connect(ServerName, UserName, PassWord) '这三项换为你自己的

PBackup.Database = DatabaseName '数据库名

Me.Cursor = System.Windows.Forms.Cursors.WaitCursor

Dim PathName As String

PathName = "D:\BackUp"

PBackup.Files = PathName

PBackup.SQLBackup(SQLSER)

SQLSER.DisConnect()

SQLSER = Nothing

Me.Cursor = System.Windows.Forms.Cursors.Default

MsgBox("成功备份了数据")

End Sub

Q2: VB.NET备份SQL数据库

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.IO;

using System.Text;

using _5dRss.Const;

using _5dRss.lib.Data.Tool;

public partial class admin_admin_dbmanage : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

//生成备份文件列表

ListBackupFiles();

if (!Page.IsPostBack)

{

Showmsg.Visible = false;

//数据库路径

lilDBPath.Text = HttpContext.Current.Request.PhysicalApplicationPath + "App_Data\\" + ConfigurationSettings.AppSettings["DBFile"];

//新建一个 FileInfo 对象，并获得数据库文件的大小，然后转换单位为KB

FileInfo myFileInfo = new FileInfo(lilDBPath.Text);

lilDBSize.Text = Convert.ToString(myFileInfo.Length/1024) + " KB";

//如果两个参数都不为空，则继续执行

if (Request.QueryString["cmd"] != null Request.QueryString["source"] != null)

{

//备份数据库原文件名

string sourceFileName = Request.QueryString["source"];

//如果 cmd 参数为 DelFile

if (Request.QueryString["cmd"].Equals("DelFile"))

{

//删除备份数据库文件

File.Delete(HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\" + sourceFileName);

//刷新备份文件列表

ListBackupFiles();

Showmsg.Visible = true;

Showmsg.Text = "div align='center' style='margin-bottom:8px;'img src='images/aL.gif' style='margin-bottom:-6px;'/span class='alertTxt'删除备份数据库成功!/spanimg src='images/aR.gif' style='margin-bottom:-6px;'//div";

}

//如果 cmd 参数为 Restore

if (Request.QueryString["cmd"].Equals("Restore"))

{

//用备份文件覆盖原文件

File.Copy(HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\" + sourceFileName, HttpContext.Current.Request.PhysicalApplicationPath + "App_Data\\" + ConfigurationSettings.AppSettings["DBFile"], true);

//刷新备份文件列表

ListBackupFiles();

Showmsg.Visible = true;

Showmsg.Text = "div align='center' style='margin-bottom:8px;'img src='images/aL.gif' style='margin-bottom:-6px;'/span class='alertTxt'还原备份数据库成功!/spanimg src='images/aR.gif' style='margin-bottom:-6px;'//div";

}

protected void lnkbtnCompactDB_Click(object sender, EventArgs e)

{

//压缩修复数据库

AccessDBtool.CompactAccessDB(SysConfig.ConnectionString, HttpContext.Current.Request.PhysicalApplicationPath + "App_Data\\" + ConfigurationSettings.AppSettings["DBFile"]);

Showmsg.Visible = true;

Showmsg.Text = "div align='center' style='margin-bottom:8px;'img src='images/aL.gif' style='margin-bottom:-6px;'/span class='alertTxt'压缩修复数据库成功!/spanimg src='images/aR.gif' style='margin-bottom:-6px;'//div";

}

protected void lnkbtnBackupDB_Click(object sender, EventArgs e)

{

string sourceFileName = HttpContext.Current.Request.PhysicalApplicationPath + "App_Data\\" + ConfigurationSettings.AppSettings["DBFile"];

string destFileName = HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\" + "Backup_";

destFileName += DateTime.Now.ToString("yyyyMMddHHmmss");

destFileName += ".mbk";

//将数据库文件Copy到Backup目录，如果有重名文件就覆盖原文件

File.Copy(sourceFileName, destFileName, true);

//生成备份文件列表

ListBackupFiles();

Showmsg.Visible = true;

Showmsg.Text = "div align='center' style='margin-bottom:8px;'img src='images/aL.gif' style='margin-bottom:-6px;'/span class='alertTxt'备份数据库成功!/spanimg src='images/aR.gif' style='margin-bottom:-6px;'//div";

}

/// summary

/// 生成备份文件列表

/// /summary

/// returns文件列表，文件详细信息及操作选项的HTML代码/returns

public void ListBackupFiles()

{

if (!Directory.Exists(HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\"))

Directory.CreateDirectory(HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\");

DirectoryInfo mydir = new DirectoryInfo(HttpContext.Current.Request.PhysicalApplicationPath + "Backup\\");

StringBuilder sb = new StringBuilder();

foreach (FileInfo f in mydir.GetFiles())

{

sb.Append("a href='backup/" + f.Name + "' target='_blank'img border='0' src='images/mdb.gif' style='margin:4px 3px -3px 0px'/" + f.Name + "/a a href='?cmd=DelFilesource=" + f.Name + "' title='删除备份文件'删除/a | a href='?cmd=Restoresource=" + f.Name + "' title='删除备份文件'还原数据库/a | " + f.Length/1024 + " KB | " + f.CreationTime + "br /");

}

lilBackupFileList.Text = sb.ToString();

}

把下面这句换成你的数据库地址：

//数据库路径

// lilDBPath.Text = HttpContext.Current.Request.PhysicalApplicationPath + "App_Data\\" + ConfigurationSettings.AppSettings["DBFile"];

Q3: VB.NET，将数据从dataset中删除了，如何更新到数据库？

需要声明使用CommandBuilder对象，你是 SQL 数据库还是 ACCESS 数据库，这两者的对象不一样的。

对于：SQL server

Dim Mybuilder As SqlCommandBuilder = New SqlCommandBuilder(da)

da.Update(dt) '使用Update方法实现更新到数据库

对于：ACCESS