Question

我正在开发一个保存股票的计划。如果ShoeID和Size已经被删除，我需要更新表的库存。否则它应该添加一个新行。

当我输入数据时，如果在之前的记录中有相同的shoeID和Size，则会更新。但是，如果我在一些记录之后添加记录，它会创建一个新记录。不更新以前的记录。

Private Sub AddStockBtn_Click(sender As Object, e As EventArgs) Handles AddStockBtn.Click
    Dim Size, Stock As Integer
    Dim stock_check As String
    Dim status As Boolean = False
    stock_check = "Pending"
    StockBindingSource.ResetBindings(True)

    Try
        Size = Integer.Parse(SizeTxt.Text)
        Stock = Integer.Parse(StockTxt.Text)
        Console.WriteLine(stock_check)
    Catch ex As Exception
        MessageBox.Show("Invalid Size or Stock")
    End Try

    If (StockBindingSource.Count = 0) Then
        StockBindingSource.AddNew()
        StockBindingSource.Current("No") = 1
        StockBindingSource.Current("ShoeID") = IDBox.Text
        For i As Integer = 0 To ShoeDataBindingSource.Count - 1
            Dim rowData As DataRowView = ShoeDataBindingSource.Item(i)
            If rowData("ShoeID").ToString = IDBox.Text Then
                StockBindingSource.Current("ShoeType") = ShoeDataBindingSource.Current("Type")
                StockBindingSource.Current("Description") = ShoeDataBindingSource.Current("Name")
            End If
        Next
        StockBindingSource.Current("Size") = Size
        StockBindingSource.Current("Stock") = Stock
        StockBindingSource.EndEdit()
        TableAdapterManager.UpdateAll(SilexDatabaseDataSet)
    Else
        For i As Integer = 0 To ShoeDataBindingSource.Count - 1
            Dim rowName As DataRowView = ShoeDataBindingSource.Item(i)
            If rowName("ShoeID").ToString = IDBox.Text And StockBindingSource.Current("Size") = Size Then
                StockBindingSource.Current("Stock") = StockBindingSource.Current("Stock") + Stock
                StockBindingSource.EndEdit()
                TableAdapterManager.UpdateAll(SilexDatabaseDataSet)
                status = True
            End If
            Console.WriteLine(ShoeDataBindingSource.Count)
            stock_check = "Loop"
        Next

        If (Not status And stock_check = "Loop") Then
            Dim no As Integer
            no = StockBindingSource.Count + 1
            StockBindingSource.AddNew()
            StockBindingSource.Current("No") = no
            StockBindingSource.Current("ShoeID") = IDBox.Text
            For i As Integer = 0 To ShoeDataBindingSource.Count - 1
                Dim rowData As DataRowView = ShoeDataBindingSource.Item(i)
                If rowData("ShoeID").ToString = IDBox.Text Then
                    StockBindingSource.Current("ShoeType") = ShoeDataBindingSource.Current("Type")
                    StockBindingSource.Current("Description") = ShoeDataBindingSource.Current("Name")
                End If
            Next
            StockBindingSource.Current("Size") = Size
            StockBindingSource.Current("Stock") = Stock
            StockBindingSource.EndEdit()
            TableAdapterManager.UpdateAll(SilexDatabaseDataSet)
        End If
    End If
End Sub

我第一次输入数据

更新了相同的数据

添加另一个数据并再次添加相同的数据，

此处有新数据更新

希望你能理解这个问题。有人帮忙。

StockBindingSource.count不会更新。它总是显示为1，除非它为空。

Answer 1

请参阅上面有关我尝试将此代码发布到评论中的评论。

Dim ShoeId As Integer = 1
Dim ShoeSize As Integer = 15
Dim Stock As Integer = 1
Dim thisRow As DataRow = Nothing

Dim dt As New DataTable
dt.Columns.Add(New DataColumn With
               {
                   .ColumnName = "Id",
                    .DataType = GetType(Integer),
                    .AutoIncrement = True,
                    .AutoIncrementSeed = 1
                })

dt.Columns.Add(New DataColumn With
               {
                    .ColumnName = "ShoeId",
                    .DataType = GetType(Integer),
                    .AutoIncrement = True
                })

dt.Columns.Add(New DataColumn With
               {
                   .ColumnName = "Size",
                   .DataType = GetType(Integer)
               })

dt.Columns.Add(New DataColumn With
               {
                   .ColumnName = "ShoeType",
                   .DataType = GetType(String)
               })
dt.Columns.Add(New DataColumn With
               {
                   .ColumnName = "Stock",
                   .DataType = GetType(Integer)
               })
dt.Rows.Add(New Object() {Nothing, 1, 15, "Shoe", 5})


bs.DataSource = dt
thisRow =
    (
        From t In CType(bs.DataSource, DataTable).AsEnumerable
        Where t.Field(Of Integer)("ShoeId") = ShoeId AndAlso t.Field(Of Integer)("Size") = ShoeSize
        Select t).FirstOrDefault

If thisRow IsNot Nothing Then
    thisRow.SetField(Of Integer)("Stock", thisRow.Field(Of Integer)("Stock") + 1)
Else
    ' add
End If

ShoeId = 2
ShoeSize = 15
thisRow =
    (
        From t In CType(bs.DataSource, DataTable).AsEnumerable
        Where t.Field(Of Integer)("ShoeId") = ShoeId AndAlso t.Field(Of Integer)("Size") = ShoeSize
        Select t).FirstOrDefault

If thisRow IsNot Nothing Then
    thisRow.SetField(Of Integer)("Stock", thisRow.Field(Of Integer)("Stock") + 1)
Else
    CType(bs.DataSource, DataTable).Rows.Add(New Object() {Nothing, ShoeId, ShoeSize, "Shoe", 5})
End If

ShoeId = 1
ShoeSize = 15
thisRow =
    (
        From t In CType(bs.DataSource, DataTable).AsEnumerable
        Where t.Field(Of Integer)("ShoeId") = ShoeId AndAlso t.Field(Of Integer)("Size") = ShoeSize
        Select t).FirstOrDefault

If thisRow IsNot Nothing Then
    thisRow.SetField(Of Integer)("Stock", thisRow.Field(Of Integer)("Stock") + 1)
Else
    CType(bs.DataSource, DataTable).Rows.Add(New Object() {Nothing, ShoeId, ShoeSize, "Shoe", 5})
End If

Answer 2

最后，我找到了一种简单的方法来完成任务。谢谢Karen的帮助。

For Each row As DataGridViewRow In StockDataGrid.Rows
            Dim tempID As String = row.Cells(1).Value
            Dim tempSize As String = row.Cells(3).Value
            If tempID = IDBox.Text And tempSize = Size Then
                StockBindingSource.Position = count
                StockBindingSource.Current("Stock") = StockBindingSource.Current("Stock") + Stock
                StockBindingSource.EndEdit()
                TableAdapterManager.UpdateAll(SilexDatabaseDataSet)
                status = True
            End If
            count = count + 1
        Next

这样，我可以解决我的问题。我使用了datagridview。

BindingSource.Count始终显示为1，除非它不是null VB.Net

2 个答案: