vb如何读取数据库一行数据？

'读取方法：

Imports System.IO

Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Me.ListBox1.Items.Clear()

Dim StrRed As StreamReader = New StreamReader("D:\111.txt", System.Text.Encoding.Default)

While Not StrRed.EndOfStream

Me.ListBox1.Items.Add(StrRed.ReadLine())

End While

StrRed.Dispose()

End Sub

End Class

'其它读写方法：

写入：

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

Dim strR As New StreamWriter("D:\111.txt", True)'参数True表示 在原来的数据上面添加，如果为False这删除原来的数据 重新写入数据

strR.WriteLine(Me.TextBox2.Text)

strR.Dispose()

End Sub

读取：

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

Dim strR As New StreamReader("D:\111.txt")

While Not strR.EndOfStream

Me.TextBox1.Text += strR.ReadLine() &vbCrLf

End While

strR.Dispose()

End Sub

你还有一段连接access数据库的代码没有。你代码里的ExecuteSQL是什么？ Dim

ExecuteSQL

As

New

ADODB.ConnectionDataPath

="你的数据库位置"ConnString

=

"Provider=Microsoft.Jet.OLEDB.4.0Data

Source="

&

DataPath

&

"Persist

Security

Info=False"

ExecuteSQL

.open

ConnString

-----------------完整代码--------------未测试---------------Private

Sub

Command1_Click()

Dim

mrc

As

ADODB.RecordsetDim

ExecuteSQL

As

New

ADODB.ConnectionDataPath

="你的数据库位置"ConnString

=

"Provider=Microsoft.Jet.OLEDB.4.0Data

Source="

&

DataPath

&

"Persist

Security

Info=False"

ExecuteSQL

.open

ConnString

txtsql

=

"select

username

from

use

where

username='"

&

Trim(Text1.Text)

&

"'"

Set

mrc

=

ExecuteSQL(txtsql)

If

mrc.EOF

=

True

Then

MsgBox

"

用户名错误！",

vbExclamation

+

vbOKOnly,

"警告"

Text1.SetFocus

Text1.SelStart

=

0

Text1.SelLength

=

Len(Text1.Text)

Exit

Sub

End

If

username

=

mrc.Fields(0)

txtsql

=

"select

username

from

use

where

password='"

&

Trim(Text2.Text)

&

"'"

Set

mrc

=

ExecuteSQL(txtsql)

If

mrc.EOF

=

True

Then

MsgBox

"

密码错误！",

vbExclamation

+

vbOKOnly,

"警告"

Text2.SetFocus

Text2.SelStart

=

0

Text2.SelLength

=

Len(Text2.Text)

Exit

Sub

End

IfMDIForm1.Show

Unload

Me

End

Sub

123456789101112131415161718192021222324252627282930313233Dim strConn As String = "Provider=Microsoft.Jet.OLEDB.4.0Data Source=" &Application.StartupPath &"\Data.mdb"Dim myConn As OleDbConnection = New OleDbConnection(strConn)Dim myComm As OleDbCommand = New OleDbCommandmyComm.Connection = myConnmyComm.CommandText = "select * from 开奖结果"'Dim myReader As OleDbDataReaderDim saveComm As OleDbCommand = New OleDbCommandmyConn.Open()For i = 1 To UBound(a)saveComm.CommandText = "insert into 开奖结果 (期号,红球1,红球2,红球3,红球4,红球5,红球6,蓝球,备注) values (@期号,@红球1,@红球2,@红球3,@红球4,@红球5,@红球6,@蓝球,@备注)"saveComm.Connection = myConnsaveComm.Parameters.Clear()saveComm.Parameters.AddWithValue("@期号", a(i).qh)saveComm.Parameters.AddWithValue("@红球1", a(i).h1)saveComm.Parameters.AddWithValue("@红球2", a(i).h2)saveComm.Parameters.AddWithValue("@红球3", a(i).h3)saveComm.Parameters.AddWithValue("@红球4", a(i).h4)saveComm.Parameters.AddWithValue("@红球5", a(i).h5)saveComm.Parameters.AddWithValue("@红球6", a(i).h6)saveComm.Parameters.AddWithValue("@蓝球", a(i).lq)saveComm.Parameters.AddWithValue("@备注", a(i).bz) 'MsgBox(a(i).qh &" " &i) TrysaveComm.ExecuteNonQuery()Catch ex As ExceptionMsgBox(Err.Description)End TryNext imyConn.Close()MsgBox("写入完毕", MsgBoxStyle.Information, "提示信息")Me.Close()

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