參數異常的錯誤，不知道該怎麼辦

Question

你好， 因此，這是一個家庭作業，並在很短的教練放棄了我。當我運行我的程序時，我收到此錯誤消息。我試着對這個綁定的代碼行進行註釋，當我運行這個程序時，它給了我下一個綁定（大約三行下）的同樣的錯誤。

我把程序發給了我的老師，他說程序運行了，但是我的表單沒有正確加載或訪問數據庫，這是我看不到的，因爲每次運行這個程序時我都會得到這個錯誤。

這個任務已經過期了，我只需要一個輪盤，但更重要的是，我真的很煩，他沒有試圖幫助我。他的迴應只是「我看不到錯誤」，即使在我給他發送屏幕截圖之後。我真的很想弄清楚什麼是錯的。我想知道它是否是我的機器，因爲它似乎只發生在我的機器上？如果有，我應該更新什麼？我將如何檢查？因爲這個，我不想失敗任何其他任務。

這裏是我的數據庫代碼的副本：

Option Strict Off 
Option Explicit On 

Imports System.Data 


Public Class DataClass 
'Declare Class Level Variables 
Private CategoryProductDataSet As CategoryProductDataSet 
Private JobsEmployeesDataSet As NORTHWNDDataSet 

'Declare table adapters for the categories form 
Private ProductsTableAdapter As _ 
    CategoryProductDataSetTableAdapters.ProductsTableAdapter 

Private CategoriesTableAdapter As _ 
    CategoryProductDataSetTableAdapters.CategoriesTableAdapter 

' Declare Table Adapters for Employees and Jobs 

Private CustomersTableAdapter As _ 
    NORTHWNDDataSetTableAdapters.CustomersTableAdapter 

Private OrdersTableAdapter As _ 
    NORTHWNDDataSetTableAdapters.OrdersTableAdapter 

Private EmployeeTableAdapter As _ 
    NORTHWNDDataSetTableAdapters.EmployeesTableAdapter 

'Declare data relation for products form 
Private ProductsToCategories As DataRelation 


'================================================================================ 

'Create new constructor for class 

Public Sub New() 

    Try 
     'Instantiate data sets 
     With Me 

      .CategoryProductDataSet = New CategoryProductDataSet 
      .JobsEmployeesDataSet = New NORTHWNDDataSet 

      'instantiate the table adapters 

      .ProductsTableAdapter = _ 
       New CategoryProductDataSetTableAdapters.ProductsTableAdapter 

      .CategoriesTableAdapter = _ 
       New CategoryProductDataSetTableAdapters.CategoriesTableAdapter 

      .CustomersTableAdapter = _ 
       New NORTHWNDDataSetTableAdapters.CustomersTableAdapter 

      .OrdersTableAdapter = _ 
       New NORTHWNDDataSetTableAdapters.OrdersTableAdapter 
      'New NORTHWNDDataSetTableAdapters.CustOrdersOrdersTableAdapter 

      .EmployeeTableAdapter = _ 
       New NORTHWNDDataSetTableAdapters.EmployeesTableAdapter 

      'assign products DataRelation to dataset 
      .ProductsToCategories = CategoryProductDataSet.Relations!ProductsToCategories 

      'Fill CategoryProductdataSet using the fill method 
      .CategoriesTableAdapter.Fill(.CategoryProductDataSet.Categories) 
      .ProductsTableAdapter.Fill(.CategoryProductDataSet.Products) 

      'Fill NORTHWNDDataSet using fill method 
      .CustomersTableAdapter.Fill(JobsEmployeesDataSet.Customers) 
      .OrdersTableAdapter.Fill(JobsEmployeesDataSet.Orders) 
      .EmployeeTableAdapter.Fill(JobsEmployeesDataSet.Employees) 


     End With 

    Catch ex As Exception 

    End Try 


End Sub 


Public Function GetJobsEmployeeDataSet() As NORTHWNDDataSet 

    'Return the dataset 
    Return JobsEmployeesDataSet 

End Function 

Public Function GetCategoryProductDataSet() As CategoryProductDataSet 

    'Return the dataset 
    Return CategoryProductDataSet 


End Function 

Public Sub UpdateDataSet(ByVal ADataSet As CategoryProductDataSet) 

    Try 
     'update child deletes 
     If CategoryProductDataSet.Products.GetChanges(DataRowState.Deleted) _ 
      IsNot Nothing Then 
      'Get changes for delted child rows 
      Dim ProductsDeletedDataTable As DataTable 
      ProductsDeletedDataTable = ADataSet.Categories.GetChanges(_ 
       DataRowState.Deleted) 
      ProductsTableAdapter.Update(ProductsDeletedDataTable 
             ) 

      'update parent rows 
      If CategoryProductDataSet.Products.GetChanges IsNot Nothing Then 
       ProductsTableAdapter.Update(ADataSet.Products) 

      End If 

      'update child rows' 
      If CategoryProductDataSet.Products.GetChanges(DataRowState.Added + _ 
                    DataRowState.Modified) IsNot _ 
                   Nothing Then 

       'Get changes for the child rows 
       Dim ProductsAddDataTable As DataTable 
       ProductsAddDataTable = ADataSet.Products.GetChanges(_ 
        DataRowState.Added + DataRowState.Modified) 
       ProductsTableAdapter.Update(ProductsAddDataTable) 

      End If 

     End If 
    Catch ex As Exception 

     MessageBox.Show("Unable to update database.", "Update Error!", _ 
         MessageBoxButtons.OK, MessageBoxIcon.Stop) 

    End Try 
End Sub 

End Class 

這裏是表單代碼的副本：

Option Strict Off 
Option Explicit On 

Imports System.Data 



Public Class ProductCategoriesForm 

'declare module level variables 
Private ProductCategories As DataClass 
Private ProductCategoriesDataSet As CategoryProductDataSet 

Private ProductsTableAdapter As _ 
    NORTHWNDDataSetTableAdapters.ProductsTableAdapter 

Private CategoriesTableAdapter As _ 
    NORTHWNDDataSetTableAdapters.CategoriesTableAdapter 

Private WithEvents ProductsBindingSource As BindingSource 
Private WithEvents CategoriesBindingSource As BindingSource 

Private AddingBoolean As Boolean 
Private ClosingBoolean As Boolean 
Private EditingBoolean As Boolean 

Private GridInitializedBoolean As Boolean 
Private ProductIDString As String 'holds product ID 


Private Sub ProductCategoriesForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _ 
    Handles MyBase.Load 

    Try 
     ProductCategories = New DataClass 
     ProductCategoriesDataSet = New CategoryProductDataSet 

     ProductCategoriesDataSet = ProductCategories.GetCategoryProductDataSet 


     'Set up binding source 
     ProductsBindingSource = New BindingSource 
     CategoriesBindingSource = New BindingSource 

     With ProductsBindingSource 
      .DataSource = ProductsBindingSource 
      .DataMember = "Products" 
      .Sort = "ProductID" 
     End With 

     With CategoriesBindingSource 
      .DataSource = CategoriesBindingSource 
      .DataMember = "ProductsToCategories" 
     End With 


    Catch ex As Exception 

    End Try 

    'Establish Record Count 
    ProductsBindingSource.MoveLast() 
    ProductsBindingSource.MoveFirst() 

    'Bind the textboxes 
    CategoryTextBox.DataBindings.Add("text", _ 
    CategoriesBindingSource, "CategoryName") 

    CategoryIDTextBox.DataBindings.Add("text", _ 
    CategoriesBindingSource, "CategoryID") 
    DescriptionTextBox.DataBindings.Add("text", _ 
    CategoriesBindingSource, "Description") 

    'Initialize binding for products data grid view 
    If Not GridInitializedBoolean Then 
     ProductDataGridView.DataSource = _ 
      ProductsBindingSource 
     SetUpGridColumns() 
     GridInitializedBoolean = True 

    End If 

    'filter products by category ID 
    ProductsBindingSource.Filter = "CategoryID = '" & _ 
    CategoryIDTextBox.Text & "'" 
End Sub 

Private Sub ProductCategoriesForm_FormClosing(ByVal sender As Object, _ 
               ByVal e As System.Windows.Forms.FormClosingEventArgs) _ 
              Handles Me.FormClosing 

    'Check for unsaved changes 
    If ProductCategoriesDataSet.HasChanges Then 
     Dim ResponseDialogResult As DialogResult 
     ResponseDialogResult = MessageBox.Show("Save the database changes?", _ 
               "Unsaved Changes", MessageBoxButtons.YesNoCancel, _ 
               MessageBoxIcon.Question) 

     Select Case ResponseDialogResult 
      Case Windows.Forms.DialogResult.Yes 
       ProductCategories.UpdateDataSet(ProductCategoriesDataSet) 
      Case Windows.Forms.DialogResult.Cancel 
       e.Cancel = True 
     End Select 
    End If 
End Sub 

'Create a sub routine to set up the grid columns and set the column widths' 

Private Sub SetUpGridColumns() 

    Try 
     With Me.ProductDataGridView 
      'Set up column headers 
      .Columns!ProductID.HeaderText = "Product ID" 
      .Columns!ProductName.HeaderText = "Product Name" 
      .Columns!SupplierID.HeaderText = "Supplier ID" 
      .Columns!CategoryID.HeaderText = "Category ID" 
      .Columns!QuanityPerUnit.HeaderText = "Quantity Per Unit" 
      .Columns!UnitPrice.HeaderText = "Unit Price" 
      .Columns!UnitsInStock.HeaderText = "Units In Stock" 
      .Columns!UnitsOnORder.HeaderText = "Units On Order" 
      .Columns!ReorderLevel.HeaderText = "Reorder Level" 
      .Columns!Discontinued.HeaderText = "Discontinued" 

      'set up column widths' 
      .Columns!ProductID.Width = 100 
      .Columns!ProductName.Width = 75 
      .Columns!SupplierID.Width = 30 
      .Columns!CategoryID.Width = 75 
      .Columns!QuanityPerUnit.Width = 35 
      .Columns!UnitPrice.Width = 50 
      .Columns!UnitsInStock.Width = 50 
      .Columns!UnitsOnORder.Width = 50 
      .Columns!ReorderLevel.Width = 50 
      .Columns!Discontinued.Width = 50 
     End With 
    Catch ex As Exception 

    End Try 
End Sub 






Private Sub FirstButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FirstButton.Click 
    'move to first record 
    ProductsBindingSource.MoveFirst() 

    'Initilize binding for products data grid view 
    If Not GridInitializedBoolean Then 
     'Bind and format the grid 
     ProductDataGridView.DataSource = _ 
      ProductsBindingSource 
     SetUpGridColumns() 
     GridInitializedBoolean = True 

    End If 

    'Filter products by category ID 
    ProductsBindingSource.Filter = "CategoryID = '" & _ 
    CategoryIDTextBox.Text & "'" 

End Sub 


Private Sub PreviousButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PreviousButton.Click 

    'move to the previous record 
    With ProductsBindingSource 
     If .Position = 0 Then 
      .MoveLast() 
     Else 
      .MovePrevious() 
     End If 

     'Initilize binding for products data grid view 
     If Not GridInitializedBoolean Then 
      'Bind and format the grid 
      ProductDataGridView.DataSource = _ 
       ProductsBindingSource 
      SetUpGridColumns() 
      GridInitializedBoolean = True 

     End If 

     'Filter products by category ID 
     ProductsBindingSource.Filter = "CategoryID = '" & _ 
     CategoryIDTextBox.Text & "'" 

    End With 
End Sub 


Private Sub NextButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NextButton.Click 
    'move to next record 
    With ProductsBindingSource 
     If .Position = .Count - 1 Then 
      .MoveFirst() 
     Else 
      .MoveNext() 
     End If 
    End With 

    'Initilize binding for products data grid view 
    If Not GridInitializedBoolean Then 
     'Bind and format the grid 
     ProductDataGridView.DataSource = _ 
      ProductsBindingSource 
     SetUpGridColumns() 
     GridInitializedBoolean = True 

    End If 

    'Filter products by category ID 
    ProductsBindingSource.Filter = "CategoryID = '" & _ 
    CategoryIDTextBox.Text & "'" 
End Sub 

Private Sub LastButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LastButton.Click 

    'Move to last record 
    ProductsBindingSource.MoveLast() 

    'Initilize binding for products data grid view 
    If Not GridInitializedBoolean Then 
     'Bind and format the grid 
     ProductDataGridView.DataSource = _ 
      ProductsBindingSource 
     SetUpGridColumns() 
     GridInitializedBoolean = True 

    End If 

    'Filter products by category ID 
    ProductsBindingSource.Filter = "CategoryID = '" & _ 
    CategoryIDTextBox.Text & "'" 
End Sub 

Private Sub ExitButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitButton.Click 

    Me.Close() 

End Sub 

Private Sub ProductsBindingSource_PositionChanged _ 
    (ByVal sender As Object, ByVal e As System.EventArgs) _ 
    Handles ProductsBindingSource.PositionChanged 

    'Display the position and number of records 
    With Me.ProductsBindingSource 
     Me.ToolStripStatusLabel1.Text = _ 
      "record " & (.Position + 1).ToString & _ 
      " of " & .Count.ToString 
    End With 

End Sub 
Private Sub AddButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AddButton.Click 

    Try 
     If AddButton.Text = "&Add" Then 

      With ProductsBindingSource 
       .EndEdit() 
       .AddNew() 
      End With 

      AddingBoolean = True 
      CategoryIDTextBox.Focus() 
      SetNavigation(False) 
      SetControlsReadOnly(False) 
      SetButtonsForEdit() 

     Else 

      'save has been clicked 
      ProductsBindingSource.EndEdit() 
      SaveDataSet() 
      ToolStripStatusLabel2.Text = "Record Saved" 
      AddingBoolean = False 
      EditingBoolean = False 
      SetNavigation(True) 
      SetControlsReadOnly(True) 
      ResetButtonsAfterEdit() 
     End If 


    Catch ex As Exception 
     'catch duplicate records and constraint violations 
     MessageBox.Show(ex.Message) 
    End Try 
End Sub 

Private Sub SetNavigation(ByVal ValueBoolean As Boolean) 
    'Set the enabled property of the navigation 
    With Me 
     .FirstButton.Enabled = ValueBoolean 
     .LastButton.Enabled = ValueBoolean 
     .NextButton.Enabled = ValueBoolean 
     .PreviousButton.Enabled = ValueBoolean 
    End With 
End Sub 

Private Sub SetControlsReadOnly(ByVal ValueBoolean As Boolean) 
    'Locks or unlocks controls 
    With Me 
     .CategoryTextBox.ReadOnly = ValueBoolean 
     .CategoryIDTextBox.ReadOnly = ValueBoolean 
     .DescriptionTextBox.ReadOnly = ValueBoolean 

    End With 
End Sub 


Private Sub SetButtonsForEdit() 
    'set up the buttons for an add or edit 
    With Me 
     .AddButton.Text = "&Save" 
     .DeleteButton.Text = "&Cancel" 
     .EditButton.Enabled = True 
     .ToolStripStatusLabel2.Text = String.Empty 

    End With 
End Sub 

Private Sub ResetButtonsAfterEdit() 
    'reset the buttons after the add or edit is completed 

    With Me 
     .AddButton.Text = "&Add" 
     .DeleteButton.Text = "&Delete" 
     .EditButton.Enabled = True 
     .ToolStripStatusLabel2.Text = String.Empty 
    End With 
End Sub 

Private Sub EditButton_Click(ByVal sender As System.Object, _ 
          ByVal e As System.EventArgs) Handles EditButton.Click 
    'Allows user to edit the current record 

    With Me 
     .EditingBoolean = True 
     .SetNavigation(False) 
     .SetControlsReadOnly(False) 
     .SetButtonsForEdit() 
    End With 
End Sub 

Private Sub DeleteButton_Click(ByVal sender As System.Object, _ 
    ByVal e As System.EventArgs) Handles DeleteButton.Click 

    'Delete the current record after confirming or cancel an add or edit 

    Dim DeleteDialogResult As DialogResult 

    With Me 
     Try 
      If .DeleteButton.Text = "&Delete" Then 
       DeleteDialogResult = MessageBox.Show("Delete this record?", _ 
                "Confirm Delete", MessageBoxButtons.YesNo, _ 
                MessageBoxIcon.Question) 
       If DeleteDialogResult = Windows.Forms.DialogResult.Yes Then 
        .ProductsBindingSource.RemoveCurrent() 
        '.ProductsTableAdapter.Update(CategoryProductDataSet.Products) 
        .ToolStripStatusLabel2.Text = "Record Deleted" 
       End If 
      Else 
       'cancel button was clicked 
       .ProductsBindingSource.CancelEdit() 
       .AddingBoolean = False 
       .EditingBoolean = False 
       .SetNavigation(True) 
       .SetControlsReadOnly(True) 
       .ResetButtonsAfterEdit() 

      End If 
     Catch ex As Exception 
      Dim Messagestring As String 
      Messagestring = "Unable to complete the delete/cancel: " _ 
       & ex.Message 
      MessageBox.Show(Messagestring, "Delete/Cancel Error", _ 
          MessageBoxButtons.OK, MessageBoxIcon.Exclamation) 
     End Try 
    End With 

End Sub 

Private Sub SaveDataSet() 
    'save the dataset back to the original data source 
    With Me 
     If .ProductCategoriesDataSet.HasChanges Then 
      Try 
       .Validate() 
       .ProductsBindingSource.EndEdit() 
       .CategoriesBindingSource.EndEdit() 
       .ProductCategories.UpdateDataSet(ProductCategoriesDataSet) 
       .ProductCategoriesDataSet.AcceptChanges() 


      Catch ex As Exception 
       MessageBox.Show("Unable to complete changes. " & ex.Message, "Save", _ 
           MessageBoxButtons.OK, MessageBoxIcon.Warning) 
      End Try 
     End If 
    End With 
End Sub 

Private Sub ProductDataGridView_CellValidating(ByVal sender As Object, _ 
               ByVal e As System.Windows.Forms.DataGridViewCellValidatingEventArgs) _ 
              Handles ProductDataGridView.CellValidating 

    'validate when the user moves to another cell in the same row 
    With Me.ProductDataGridView 
     'Dont validate if the form is closing 
     If Not ClosingBoolean Then 
      'check for valid product ID 
      If .Columns(e.ColumnIndex).Name = "ProductID" Then 
       Dim EnteredDate As Date 
       If Not Date.TryParse(_ 
        e.FormattedValue.ToString, EnteredDate) Then 
        ShowCellError(.CurrentCell, _ 
            "Product ID must be entered in a valid format.") 
        e.Cancel = True 
       Else 
        ClearCellError(.CurrentCell) 

       End If 
      ElseIf e.FormattedValue.ToString = String.Empty Then 
       ShowCellError(.CurrentCell, "Entry Needed.") 
       e.Cancel = True 
      Else 
       ClearCellError(.CurrentCell) 
      End If 
     End If 
    End With 
End Sub 


Private Sub ShowCellError(ByVal CurrentCell As DataGridViewCell, _ 
    ByVal MessageString As String) 

    'Displays a message if there is an error in the cell 
    CurrentCell.ErrorText = MessageString 
    Me.ProductDataGridView.ShowCellErrors = True 


End Sub 

Private Sub ClearCellError(ByVal CurrentCell As DataGridViewCell) 

    'Clear previous error messages displayed in the current cell 
    CurrentCell.ErrorText = String.Empty 
    Me.ProductDataGridView.ShowCellErrors = False 

End Sub 

Private Sub ProductDataGridView_DataError(ByVal sender As Object, _ 
    ByVal e As System.Windows.Forms.DataGridViewDataErrorEventArgs) _ 
    Handles ProductDataGridView.DataError 

    'Allow an add to be cancelled 
    Dim CurrentRow As DataGridViewRow = ProductDataGridView.Rows(e.RowIndex) 

    If CurrentRow.Cells(0).Value Is DBNull.Value Then 
     ProductsBindingSource.CancelEdit() 
    End If 


End Sub 

Private Sub ProductsBindingSource_DataError(ByVal sender As Object, _ 

BYVALË作爲System.Windows.Forms.BindingManagerDataErrorEventArgs）_ 把手ProductsBindingSource.DataError

'Allow a user to cancel a requested add 
    If ProductDataGridView.CurrentRow.Cells(0) Is DBNull.Value Then 
     ProductsBindingSource.CancelEdit() 
    End If 

End Sub 

'Validate grid data 

Private Sub ProductDataGridView_KeyUp(ByVal sender As Object, _ 
    ByVal e As System.Windows.Forms.KeyEventArgs) _ 
    Handles ProductDataGridView.KeyUp 

    'Check to see if Esc key was pressed in the grid 
    'Needed to quit an add action 

    If e.KeyData = Keys.Escape Then 
     Me.ProductsBindingSource.CancelEdit() 
     With Me.ProductDataGridView 
      .ShowCellErrors = False 
      .ShowRowErrors = False 
     End With 
    End If 

End Sub 

Private Sub ProductDataGridView_RowValidating(ByVal sender As Object, _ 

ByVal e As Sy stem.Windows.Forms.DataGridViewCellCancelEventArgs）_ 把手ProductDataGridView.RowValidating

'Validate moves to another row 
    Dim ErrorFoundBoolean As Boolean = False 
    Dim MessageString As String 

    With Me.ProductDataGridView 
     'Skip validation if the form is closing 
     If Not ClosingBoolean Then 
      Dim CurrentRow As DataGridViewRow = .Rows(e.RowIndex) 
      'Walk through the rows 
      For Each CheckCell As DataGridViewCell In CurrentRow.Cells 
       If .Columns(CheckCell.ColumnIndex).Name = "hire_date" Then 
        Dim TestDate As Date 
        If Not Date.TryParse(CheckCell.FormattedValue, TestDate) Then 
         MessageString = "Invalid date format for Date Hired." 
         ShowRowError(CheckCell, MessageString) 
         ErrorFoundBoolean = True 
        End If 
       ElseIf CheckCell.FormattedValue.ToString = String.Empty Then 
        'Every Column must have an entry 
        Dim ColumnHeaderText As String = _ 
         .Columns(CheckCell.ColumnIndex).HeaderText 
        MessageString = ColumnHeaderText & " is a required entry." 
        ShowRowError(CheckCell, MessageString) 
        ErrorFoundBoolean = True 
        Exit For 
       End If 
      Next 

      If ErrorFoundBoolean Then 
       e.Cancel = True 
      Else 
       ClearRowError(CurrentRow.Cells(0)) 
      End If 
     End If 
    End With 

End Sub 

Private Sub ShowRowError(ByVal CurrentCell As DataGridViewCell, _ 
    ByVal MessageString As String) 

    'Display a message for the row in error 

    With Me.ProductDataGridView 
     .Rows(CurrentCell.RowIndex).ErrorText = MessageString 
     .ShowRowErrors = True 
    End With 

End Sub 


Private Sub ClearRowError(ByVal CurrentCell As DataGridViewCell) 

    'Clear messages following delivery 

    With Me.ProductDataGridView 
     .Rows(CurrentCell.RowIndex).ErrorText = String.Empty 
     .ShowRowErrors = False 
    End With 
End Sub 

Private Sub CategoryTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CategoryTextBox.TextChanged 

End Sub 
End Class 

Answer 1

一個BindingSource的對象的DataSource屬性是不是想做好自己。假設它是用於綁定的對象（object/list/observable collection/etc）。

With CategoriesBindingSource 
     .DataSource = CategoriesBindingSource '<--- Here 
     .DataMember = "ProductsToCategories" 
    End With 

舉例來說，如果你有一個Person類，你有這樣的事情：

Dim bob as New Person 

With PersonBindingSource 
    .DataSource = bob 
    .DataMember = "FirstName" 
End With 

以下是關於DataSource屬性更多的相關信息：

http://msdn.microsoft.com/en-us/library/system.windows.forms.bindingsource.datasource.aspx