VB.net Postgresql调用，NpgsqlDataReader，NpgsqlDataAdapter的调用例子。

VB环境调用Npgsql包读取数据库的例子太少了。在网上找了好久都没找到例子。

NpgsqlDataReader的使用方法，查询字段信息。

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

        If TextBox1.Text = "" Then
            MessageBox.Show("请填写ID")
            Exit Sub
        End If


        Dim cn As New NpgsqlConnection
        Dim scmd As New NpgsqlCommandDim dr As NpgsqlDataReaderDim strSSQL As String
        Try
            cn.ConnectionString = "Server=192.168.1.101;Port=5432;User Id=admin;Password=admin;Database=db;"
            cn.Open()
            strSSQL = "SELECT dataname  FROM   public.datainfo where datasyu = '" + TextBox1.Text + "'"
            scmd.Connection = cn
            scmd.CommandText = strSSQL
            dr = scmd.ExecuteReader()

            If (dr.HasRows) Then

                While (dr.Read())
                    'MessageBox.Show(dr(0))
                    TextBox2.Text = dr(0)
                End While


            End If
        Catch ex As Exception
            Throw ex
        Finally
            cn.Close()
            dr = Nothing
            scmd = Nothing
            cn = Nothing
        End Try
end sub

　　

NpgsqlDataAdapter 的使用方法，查询结果集信息。

    Public conn As NpgsqlConnection = New NpgsqlConnection("Server=192.168.1.101;Port=5432;User Id=admin;Password=admin;Database=db;")

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

        If TextBox1.Text = "" Then
            MessageBox.Show("请输入ID")
            Exit Sub
        End If


        Dim Sql2 = "SELECT colno ,colname  FROM   public.datacolinfo where datasyu = '" + TextBox1.Text + "'"
        Dim dt As DataTable = New DataTable()
        Dim da As NpgsqlDataAdapter = New NpgsqlDataAdapter(Sql2, conn)
        da.Fill(dt)
        DataGridView1.AutoGenerateColumns = True
        DataGridView1.DataSource = dt

    End Sub

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