1. VB.net鏈接Mysql資料庫的方法
sqlcommand = 「select count( *) from user where User="+輸入的User信息+"」；
如果執行這個語句返回的值大於0
說明資料庫中存在此用戶
2. 請問：VB.NET怎麼連接SQL
Public sqlcon As System.Data.SqlClient.SqlConnection
Public sqladapter As System.Data.SqlClient.SqlDataAdapter
Public command As System.Data.SqlClient.SqlCommand
Public ds As System.Data.DataSet
Public dr As System.Data.DataTable
sqlcon = New System.Data.SqlClient.SqlConnection
sqlcon.ConnectionString = "Server=(local); Initial Catalog=test1 ; User ID="資料庫sa用戶"; Password="資料庫密碼""
ds = New System.Data.DataSet
dr = New System.Data.DataTable(" test2 ")
ds.Tables.Add(dr)
sqladapter = New System.Data.SqlClient.SqlDataAdapter("select * from test2 ", sqlcon)
sqlcon.Open()
sqladapter.Fill(dr)
sqlcon.Close()
界面上控制項
DataGridView1.DataSource = dr
3. vb.net 連接sql資料庫模塊,如何使用
比如有個asp.net(vb.net)連接sql server 2000資料庫的連接模塊(mole)：
Mole MdlCommon
Public txtSQL As String '存放SQL語句
Public DBSet As DataSet '查詢得到的記錄集
Public ErrorMsg As String '存放錯誤信息
Public Function ExecuteSQL(ByVal strSQL As String, ByRef errMsg As String) As DataSet
Dim cnn As SqlClient.SqlConnection
Dim cmd As New SqlClient.SqlCommand()
Dim adpt As SqlClient.SqlDataAdapter
Dim rst As New DataSet()
Dim SplitSQL() As String
errMsg = ""
Try
SplitSQL = Split(strSQL)
cnn = New SqlClient.SqlConnection("data source=(local);initial catalog=urp;user id=sa;pwd=1234")
If InStr("INSERT,DELETE,UPDATE", UCase$(SplitSQL(0))) Then
cmd.Connection = cnn
cmd.Connection.Open()
cmd.CommandText = strSQL
cmd.ExecuteNonQuery()
Else
adpt = New SqlClient.SqlDataAdapter(strSQL, cnn)
adpt.Fill(rst)
ExecuteSQL = rst
End If
Catch ex As Exception
errMsg = ex.Message
Finally
rst = Nothing
cnn = Nothing
End Try
End Function End Mole
調用時在asp.net後台寫上txtSQL="SELECT * FROM user";
DBSet=ExecuteSQL(txtSQL,ErrorMsg)就可以查詢db返回結果了。