system.dll

Question

我一直有这个错误

＆＃34; system.dll中发生了system.data.sqlclient.sqlexception类型的未处理异常

我似乎无法找到我失踪的东西而且它指向我的

Private Sub Check_Info()                        
etc..
etc...
etc.
dDA.FILL(dDS) '<<

注意： 我的SQLserver正在运行，运行连接的表也没问题。 代码

#Region " Variable Declarations "

    Public sConn As SqlConnection
    Dim eDS As DataSet = New DataSet
    Dim eDA As SqlDataAdapter = New SqlDataAdapter
    Dim eDR As DataRow
    Dim dDS As DataSet = New DataSet
    Dim dDA As SqlDataAdapter = New SqlDataAdapter
    Dim dDR As DataRow
    'Public bExitApplication As Boolean

#End Region

#Region " User-defined Procedures "

    Private Sub Check_Info()
        sConn.Open()
        eDA.SelectCommand = New SqlCommand("SELECT emp_fname,emp_lname,emp_mname FROM tblEmployee WHERE emp_idno='" & TextBox1.Text.ToString & "' and emp_pass='" & TextBox2.Text & "'", sConn)
        eDS.Clear()
        eDA.Fill(eDS)
        If eDS.Tables(0).Rows.Count > 0 Then
            eDR = eDS.Tables(0).Rows(0)
            TextBox3.Text = eDR("emp_lname") & ", " & eDR("emp_fname") & " " & eDR("emp_mname")
            dDA.SelectCommand = New SqlCommand("SELECT * FROM tblDTR WHERE emp_idno='" & TextBox1.Text & "' AND date_timein=#" & Format(Now, "MM/d/yyyy") & "# AND time_timeout IS NULL", sConn)
            dDS.Clear()
            dDA.Fill(dDS)

            If dDS.Tables(0).Rows.Count > 0 Then
                dDR = dDS.Tables(0).Rows(0)
                Button1.Enabled = True
                Button1.Text = "&Time Out"
                TextBox4.Text = Format(dDR("time_timein"), "h:mm:ss tt")
            Else
                Button1.Enabled = True
                Button1.Text = "&Time In"
            End If
            dDR = Nothing
            dDS.Dispose()
            dDA.Dispose()
        Else
            TextBox3.Clear()
            TextBox4.Clear()
            TextBox5.Clear()
            Button1.Enabled = False
        End If
        eDR = Nothing
        eDS.Dispose()
        eDA.Dispose()
        sConn.Close()
    End Sub

    Private Sub ReturnFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox3.GotFocus, TextBox4.GotFocus, TextBox5.GotFocus
        TextBox1.Focus()
    End Sub

    Private Sub TextboxChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged, TextBox2.TextChanged
        If (TextBox1.Text <> "" And TextBox2.Text <> "") Then
            Check_Info()
        End If
    End Sub

    Private Sub LoginGotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.GotFocus, TextBox2.GotFocus
        TextBox3.Clear()
        TextBox4.Clear()
        TextBox5.Clear()
    End Sub
#End Region

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        sConn = New SqlConnection("Data Source=(localdb)\Projects;Initial Catalog=StudInfo;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False")
        Label2.Text = Format(Now, "MMMM d, yyyy  h:mm:ss tt")
        Timer1.Enabled = True
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Label2.Text = Format(Now, "MMMM d, yyyy  h:mm:ss tt")
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        ' Time-in and Time-out button
        Dim strSQL As String
        sConn.Open()
        If Button1.Text = "&Time In" Then
            dDR = dDS.Tables(0).NewRow()
            TextBox4.Text = Format(Now, "h:mm:ss tt")
            strSQL = "INSERT INTO tblDTR (emp_idno, date_timein, time_timein) VALUES ('" & TextBox1.Text & "', #" & Format(Now, "MM/d/yyyy") & "#, #" & TextBox4.Text & "#)"
            Button1.Text = "&Time Out"
        Else
            TextBox5.Text = Format(Now, "h:mm:ss tt")
            strSQL = "UPDATE tblDTR SET time_timeout=#" & TextBox5.Text & "# WHERE emp_idno='" & TextBox1.Text & "' AND date_timein=#" & Format(Now, "MM/d/yyyy") & "# and time_timein=#" & TextBox4.Text & "#"
            Button1.Text = "&Time In"
        End If
        Dim dCmd As SqlCommand = New SqlCommand(strSQL, sConn)
        dCmd.ExecuteNonQuery()
        dCmd.Dispose()

        dDR = Nothing
        dDS.Dispose()
        dDA.Dispose()
        sConn.Close()
        Button1.Enabled = False
        TextBox1.Clear()
        TextBox2.Clear()
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        ' clear the form
        TextBox1.Clear()
        TextBox2.Clear()
        TextBox3.Clear()
        TextBox4.Clear()
        TextBox5.Clear()
        Button1.Text = "&Time In"
        Button1.Enabled = False
        TextBox1.Focus()
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        ' System Administration
        bExitApplication = True
        Dim f As Form
        f = New UserLogin
        Me.Close()
        f.Show()

    End Sub

    Private Sub Form1_Closing(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
        If Not bExitApplication Then
            MsgBox("You cannot close the system this way..." & vbCrLf & vbCrLf & "Please Quit the application in the System Administration Module or by clicking Exit in the bottom of this window.", MsgBoxStyle.Critical + MsgBoxStyle.OkOnly, "Error: No Administrative Privilage")
            e.Cancel = True
        End If
    End Sub

    Private Sub Label7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label7.Click

    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        MsgBox("Thank you for using Attandance Monitoring System")
        bExitApplication = True
        Application.Exit()
    End Sub
End Class

Answer 1

几乎可以肯定的是：

...date_timein=#" & Format(Now, "MM/d/yyyy") & "#...

你没有生成VB代码，你是生成的SQL代码，所以不要在字符串文字中使用＃。正确的方法是输入一个参数：

dDA.SelectCommand = New SqlCommand("SELECT * FROM tblDTR WHERE emp_idno=@EmpID AND date_timein=@Today AND time_timeout IS NULL", sConn)
cmd.Parameters.Add("@Today",DbType.DateTime).Value = DateTime.Now
cmd.Parameters.Add("@EmpID",DbType.Int).Value = TextBox1.Text