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vb.net数据库流程

作者:小编 更新时间:2023-08-22 08:03:44 浏览量:420人看过

如何用vb.net查询、添加、删除、修改数据库(需要很详细的代码)?

sQueryString是SQL(增删查改)语句

public

Boolean

ExecSQL(string

sQueryString)

{

SqlConnection

con

=

new

SqlConnection(ConfigurationManager.AppSettings["conStr"]);

con.Open();

SqlCommand

dbCommand

SqlCommand(sQueryString,

con);

try

dbCommand.ExecuteNonQuery();

con.Close();

}

catch

return

false;

true;

建立一个类,明自己取,然后调用就是了

例如:

BC=NEW

类();

STRING

ist="INSERT

INTO

BC.ExecSQL(ist);

就可以了

vb.net数据库操作

参考一下下面这段代码就可以了.

Imports System.Data

'引入数据库操作类命名空间

Imports System.Data.OleDb

'引入ADO.NET操作命名空间

Public Class FrmModifystInfo

Inherits System.Windows.Forms.Form

Public ADOcmd As OleDbDataAdapter

Public ds As DataSet = New DataSet()

'建立DataSet对象

Public mytable As Data.DataTable

'建立表单对象

Public myrow As Data.DataRow

'建立数据行对象

Public rownumber As Integer

'定义一个整型变量来存放当前行数

Public SearchSQL As String

Public cmd As OleDbCommandBuilder

'======================================================

#Region " Windows 窗体设计器生成的代码 "

#End Region

Private Sub FrmModifystInfo_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load

'窗体的载入

TxtSID.Enabled = False

TxtName.Enabled = False

ComboSex.Enabled = False

TxtBornDate.Enabled = False

TxtClassno.Enabled = False

TxtRuDate.Enabled = False

TxtTel.Enabled = False

TxtAddress.Enabled = False

TxtComment.Enabled = False '设置信息为只读

Dim tablename As String = "student_Info "

SearchSQL = "select * from student_Info "

ExecuteSQL(SearchSQL, tablename) '打开数据库

ShowData() '显示记录

End Sub

Private Sub ShowData()

'在窗口中的textbox中显示数据

myrow = mytable.Rows.Item(rownumber)

TxtSID.Text = myrow.Item(0).ToString

TxtName.Text = myrow.Item(1).ToString

Private Sub BtFirst_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtFirst.Click

'指向第一条数据

rownumber = 0

ShowData()

Private Sub BtPrev_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtPrev.Click

'指向上一条数据

BtNext.Enabled = True

rownumber = rownumber - 1

If rownumber 0 Then

rownumber = 0 '如果到达记录的首部,行号设为零

BtPrev.Enabled = False

End If

Private Sub BtNext_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtNext.Click

BtPrev.Enabled = True

rownumber = rownumber + 1

If rownumber mytable.Rows.Count - 1 Then

rownumber = mytable.Rows.Count - 1 '判断是否到达最后一条数据

BtNext.Enabled = False

Private Sub BtLast_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtLast.Click

'指向最后一条数据

rownumber = mytable.Rows.Count - 1

Private Sub BtDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtDelete.Click

mytable.Rows.Item(rownumber).Delete() '删除记录

If MsgBox( "确定要删除改记录吗? ", MsgBoxStyle.OKCancel + vbExclamation, "警告 ") = MsgBoxResult.OK Then

cmd = New OleDbCommandBuilder(ADOcmd)

'使用自动生成的SQL语句

ADOcmd.Update(ds, "student_Info ")

BtNext.PerformClick()

Private Sub BtModify_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtModify.Click

TxtSID.Enabled = False '关键字段只读

TxtName.Enabled = True '可读写

ComboSex.Enabled = True

TxtBornDate.Enabled = True

TxtClassno.Enabled = True

TxtRuDate.Enabled = True

TxtTel.Enabled = True

TxtAddress.Enabled = True

TxtComment.Enabled = True

Private Sub BtUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtUpdate.Click

If Not Testtxt(TxtName.Text) Then

MsgBox( "请输入姓名! ", vbOKOnly + vbExclamation, "警告 ")

TxtName.Focus()

Exit Sub

If Not Testtxt(ComboSex.Text) Then

MsgBox( "请选择性别! ", vbOKOnly + vbExclamation, "警告 ")

ComboSex.Focus()

If Not Testtxt(TxtClassno.Text) Then

MsgBox( "请选择班号! ", vbOKOnly + vbExclamation, "警告 ")

TxtClassno.Focus()

If Not Testtxt(TxtTel.Text) Then

MsgBox( "请输入联系电话! ", vbOKOnly + vbExclamation, "警告 ")

TxtTel.Focus()

If Not Testtxt(TxtAddress.Text) Then

MsgBox( "请输入家庭住址! ", vbOKOnly + vbExclamation, "警告 ")

TxtAddress.Focus()

If Not IsNumeric(Trim(TxtSID.Text)) Then

MsgBox( "请输入数字学号! ", vbOKOnly + vbExclamation, "警告 ")

TxtSID.Focus()

If Not IsDate(TxtBornDate.Text) Then

MsgBox( "出生时间应输入日期格式(yyyy-mm-dd)! ", vbOKOnly + vbExclamation, "警告 ")

TxtBornDate.Focus()

If Not IsDate(TxtRuDate.Text) Then

MsgBox( "入校时间应输入日期格式(yyyy-mm-dd)! ", vbOKOnly + vbExclamation, "警告 ")

TxtRuDate.Focus()

myrow.Item(0) = Trim(TxtSID.Text)

myrow.Item(1) = Trim(TxtName.Text)

mytable.GetChanges()

'对数据库进行更新

MsgBox( "修改学籍信息成功! ", vbOKOnly + vbExclamation, "警告 ")

TxtComment.Enabled = False '重新设置信息为只读

Private Sub BtCancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtCancel.Click

TxtComment.Enabled = False

Public Function ExecuteSQL(ByVal SQL As String, ByVal table As String)

Try

'建立ADODataSetCommand对象

'数据库查询函数

ADOcmd.Fill(ds, table) '取得表单

mytable = ds.Tables.Item(0) '取得名为table的表

rownumber = 0 '设置为第一行

'取得第一行数据

Catch

MsgBox(Err.Description)

End Try

End Function

End Class

vb.net 怎么操作数据库

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 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

VB.NET通过调用模块怎么建立access数据库?

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