Question

需要将记录添加到tblMeetings表，然后从tblMeetings获取该ID列（PK，Int，no null）以将tblVotings表添加到Meeting_ID列（int，not null）。前2个查询代码块工作！最后一个受保护的子＆＃34; ftrInsert_Click＆＃34;我试图将参数从一个表传递到另一个表时，块不起作用。我没有收到错误，记录插入到tblMeetings但不插入tblVotings。我的整个aspx.vb代码页：

Imports System
Imports System.Data
Imports System.Data.SqlClient

Partial Class _NewMeetings
Inherits System.Web.UI.Page

Dim WithEvents ftrInsert As New Button

Protected Sub GridView2_RowCommand(ByVal sender As System.Object, ByVal e As           System.Web.UI.WebControls.GridViewCommandEventArgs)
    If e.CommandName = "ftrInsert" Then
        'call the insert sub (sender is the gridview that called the rowCommand, 
        'UsersDS is the name of our sqlDataSource on the page
        gvQuickInsert(sender, SqlDataSource2)
    End If
End Sub

Protected Sub gvQuickInsert(ByRef gv As GridView, ByRef ds As SqlDataSource)
    Dim paramsArr As ArrayList = New ArrayList
    Dim controlsArr As ArrayList = New ArrayList
    Dim col As Integer = 0
    Dim footrow As GridViewRow = gv.FooterRow

    Try
        Dim ix As Integer = 0
        For ix = 0 To gv.Columns.Count
            Dim d As DataControlField = gv.Columns(ix)
            If d.InsertVisible = True Then
                If footrow.Cells(ix).Controls(1) IsNot Nothing Then
                    paramsArr.Add(d.SortExpression.ToString)
                controlsArr.Add(footrow.Cells(ix).Controls(1))
                End If
            End If
        Next
    Catch ex As Exception
    End Try

    ds.InsertParameters.Clear()

    Dim ii As Integer = 0
    For Each contr As Object In controlsArr
        If contr.GetType.Name.ToLower.Contains("textbox") Then
            ds.InsertParameters.Add(paramsArr(ii), TryCast(contr, TextBox).Text)
        ElseIf contr.GetType.Name.ToLower.Contains("dropdownlist") Then
            ds.InsertParameters.Add(paramsArr(ii), _
          TryCast(contr, DropDownList).SelectedValue)
        ElseIf contr.GetType.Name.ToLower.Contains("checkbox") Then
            If TryCast(contr, CheckBox).Checked Then
                ds.InsertParameters.Add(paramsArr(ii), 1)
            Else
                ds.InsertParameters.Add(paramsArr(ii), 0)
            End If
        End If
        ii = ii + 1
    Next
    ds.Insert()
    gv.DataBind()
End Sub
Protected Sub ftrInsert_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ftrInsert.Click

    Dim strConnection As String = ConfigurationManager.ConnectionStrings("ServiceLine_CommitteeConnectionString").ConnectionString
    Using con As New SqlConnection(strConnection)

        'Dim cmd As New SqlCommand("INSERT INTO tblVotings VALUES (@
        Dim Meeting_ID As New SqlParameter("@ID", SqlDbType.Int)
        Dim Committee_ID As New SqlParameter("@Comm", SqlDbType.Int)
        Dim Member_Name As New SqlParameter("@Member", SqlDbType.NVarChar)

        'Dim con As New SqlConnection(strConnection)
        Dim cmd As New SqlCommand("INSERT INTO tblVotings(Meeting_ID, Committee_ID, Member_Name) SELECT M.ID AS Meeting_ID, C.ID AS Committee_ID, CM.Full_Name AS Member_Name FROM tblCommitteeName AS C INNER JOIN tblMeetings AS M ON M.ContractCategory = C.Contract_Category AND M.Committee = C.Committee_Name INNER JOIN tblCommitteeMembers AS CM ON CM.Committee = M.Committee WHERE (M.ID IN (@ID)) and (C.ID IN (@Comm)) and (CM.Full_Name IN (@Member))", con)

        Meeting_ID.Value = 1
        Committee_ID.Value = 1
        Member_Name.Value = 1

        cmd.Parameters.Add(Meeting_ID)
        cmd.Parameters.Add(Committee_ID)
        cmd.Parameters.Add(Member_Name)
        cmd.Connection = con

        cmd.CommandType = CommandType.Text

        If con.State <> ConnectionState.Open Then con.Open()

        Dim result As Integer = cmd.ExecuteNonQuery()
        If con.state = ConnectionState.Open Then con.Close()
    End Using
End Sub

结束班

Answer 1

在SQL语句中使用参数非常简单，但有一些规则需要记住。

必须按照它们在SQL语句中出现的顺序将参数添加到命令
参数名称必须与SQL
参数大小应与数据库中给出的值相匹配。对数字不是很重要，但对字符串非常重要。

最常见的是那些新参与SQL参数的人会遇到的三个问题。

以下是使用SQL参数的示例，您应该能够剖析以获得所需内容。

Dim strConnection As String = "ConnString"
Using con As New SqlConnection(strConnection)
    Dim cmd As New SqlCommand("INSERT INTO tbl(Col1) VALUES (@p_Para1)", con)
    Dim p As New SqlParameter("@p_Para1", SqlDbType.Int, 8)
    p.value = 1
    cmd.Parameters.Add(p)

    cmd.CommandType = CommandType.Text

    If con.State <> ConnectionState.Open Then con.Open()

    cmd.ExecuteNonQuery()

    If con.State = ConnectionState.Open Then con.Close()
End Using

您的第二个错误（“无效的列名称'Meeting_ID'。无效的列名'委员会_ID'。无效的列名'Member_Name'。”）我认为这是因为您设置了WHERE子句的方式。

所以而不是：

INSERT INTO tblVotings(Meeting_ID, Committee_ID, Member_Name) 
    SELECT M.ID AS Meeting_ID, C.ID AS Committee_ID, CM.Full_Name AS Member_Name 
    FROM tblCommitteeName AS C INNER JOIN tblMeetings AS M ON M.ContractCategory = C.Contract_Category AND M.Committee = C.Committee_Name INNER JOIN tblCommitteeMembers AS CM ON CM.Committee = M.Committee 
    WHERE (Meeting_ID IN (@ID)) and (Committee_ID IN (@Comm)) and (Member_Name IN (@Member))

尝试：

INSERT INTO tblVotings(Meeting_ID, Committee_ID, Member_Name) 
    SELECT M.ID AS Meeting_ID, C.ID AS Committee_ID, CM.Full_Name AS Member_Name 
    FROM tblCommitteeName AS C INNER JOIN tblMeetings AS M ON M.ContractCategory = C.Contract_Category AND M.Committee = C.Committee_Name INNER JOIN tblCommitteeMembers AS CM ON CM.Committee = M.Committee 
    WHERE (M.ID IN (@ID)) and (C.ID IN (@Comm)) and (CM.Full_Name IN (@Member))

如何在ASP.NET页面中向代码添加参数

1 个答案: