Question

我正在尝试使用以下代码将记录插入Access数据库：

<script runat="server">
    Dim dbConnection As OleDbConnection
    Dim dbCommand As OleDbCommand
    Dim dbReader As OleDbDataReader
    Dim sqlString As String

    Sub page_load()
        Try
            txtFName.Text = ""
            txtLName.Text = ""

            dbConnection = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;data source=" & Server.MapPath("MyDatabase.accdb"))
            dbConnection.Open()

            sqlString = "SELECT * FROM table1 ORDER BY ID"
            dbCommand = New OleDbCommand(sqlString, dbConnection)
            dbReader = dbCommand.ExecuteReader()

            While dbReader.Read()
                Dim lblName As Label = New Label()
                lblName.ID = dbReader("ID")
                lblName.Text = "<b>Name: </b>" & dbReader("F_Name") & " " & dbReader("L_Name") & "<br/><br/>"
                lblName.EnableViewState = False
                nameArea.Controls.Add(lblName)
            End While

            dbReader.Close()
        Finally
            dbConnection.Close()
        End Try
    End Sub

    Sub addToDatabase()
        Try
            dbConnection.Open()
            sqlString = "INSERT INTO table1 (F_Name,L_Name) VALUES (@FName, @LName)"
            dbCommand.CommandText = sqlString
            dbCommand.Parameters.AddWithValue("@FName", txtFName.Text)
            dbCommand.Parameters.AddWithValue("@LName", txtLName.Text)
            dbCommand.ExecuteNonQuery()
        Finally
            dbConnection.Close()
        End Try
    End Sub
</script>

在我的下面的asp代码中，我有两个TextBox来保存名字和姓氏，以及一个在点击时调用addToDatabase的按钮，以及一个占位符来显示从数据库中提取的每个记录：

<asp:TextBox ID="txtFName" runat="server" />
<asp:TextBox ID="txtLName" runat="server" />
<asp:Button ID="btnSubmit" Text="Submit" OnClick="addToDatabase" runat="server" />
<br />
<asp:PlaceHolder ID="nameArea" runat="server" />

我的访问数据库包含一个名为table1的表，其中包含ID，F_Name和L_Name字段，其DataType分别为AutoNumber，Text和Text。

我的问题是当我点击btnSubmit时，它会在我的数据库中为F_Name和L_Name添加空白记录而不是TextBox中的内容，并在每次浏览器刷新时继续添加空白记录。

发生了什么事？

Answer 1

从page_load方法中删除以下行。

        txtFName.Text = ""
        txtLName.Text = ""

在addToDatabase方法的末尾添加以下内容。然后，这将显示页面中的新名称，而无需调用数据库。

Dim lblName As Label = New Label()
lblName.ID = dbReader("ID")
lblName.Text = "<b>Name: </b>" & txtFName.Text & " " & txtLName.Text & "<br/><br/>"
lblName.EnableViewState = False
nameArea.Controls.Add(lblName)

Answer 2

我移动了我的代码并添加了一个新的Sub来获取名称，然后在初始page_load和调用addToDatabase之后调用该方法。我把asp中的其他所有内容都保存在同一个下面。

Dim dbConnection As OleDbConnection
Dim dbCommand As OleDbCommand
Dim dbReader As OleDbDataReader
Dim sqlString As String

Sub page_load()
    dbConnection = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;data source=" & Server.MapPath("MyDatabase.accdb"))
    dbCommand = New OleDbCommand("", dbConnection)

    If Not Page.IsPostBack Then
        showNames()
    End If
End Sub

Sub showNames()
    Try
        dbConnection.Open()

        sqlString = "SELECT * FROM table1 ORDER BY ID"
        dbCommand.CommandText = sqlString
        dbReader = dbCommand.ExecuteReader()

        While dbReader.Read()
            Dim lblName As Label = New Label()
            lblName.ID = dbReader("ID")
            lblName.Text = "<b>Name: </b>" & dbReader("F_Name") & " " & dbReader("L_Name") & "<br/>"
            lblEntry.EnableViewState = False
            nameArea.Controls.Add(lblName)
        End While

        dbReader.Close()
    Finally
        dbConnection.Close()
    End Try
End Sub

Sub addToDatabase(src As Object, args as EventArgs)
    Try
        dbConnection.Open()
        sqlString = "INSERT INTO table1 (F_Name,L_Name) VALUES (@FName, @LName)"
        dbCommand.CommandText = sqlString
        dbCommand.Parameters.AddWithValue("@FName", txtFName.Text)
        dbCommand.Parameters.AddWithValue("@LName", txtLName.Text)
        dbCommand.ExecuteNonQuery()
    Finally
        dbConnection.Close()
    End Try

    showNames()
End Sub

将记录插入Access数据库会产生空行

2 个答案: