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从数据网格视图计算数据

datagridviewcolumn vb.net-2010 datagridview ms-access vb.net

Ans · 技术社区 · 12 年前

我一整天都在试图找到这个问题的解决方案,但我无法自己想出解决方案,也无法在网上找到。

我的问题如下:我正在vb.net 2010中创建一个应用程序,我有一个连接到该项目的Access数据库。这个数据库有两个表,一个是Representative,另一个是Demos。我试图提供一些关于代表的有用统计数据,如总Demos、总销售金额(CPO)、总建议、总Demos Given和总Demos Sold。我成功地让前三个开始工作,但没能让最后两个开始工作。这个的问题是,输入到字段中的数据是一个简单的“是”或“否”,我不知道如何输入代码,如果单元格的值是“是”,则向计数器加1,如果是“否”则向不同的计数器加1。

这是到目前为止我拥有的适用于前3个Stats的代码。

'To calculate the total demos when you change the Representative
    Dim row As Cutco_testDataSet.DemosRow

    Dim intTotalItems As Integer
    For Each row In Cutco_testDataSet.Demos.Rows
        intTotalItems += 1
    Next
    lblTotalItems.Text = intTotalItems.ToString

    'Declare the variables for the values to be stored and later displayed
    Dim intTotalCPO As Integer
    Dim intTotalRecs As Integer

    'to look in Demosdgv and add the corresponding data
    For i As Integer = 0 To Cutco_testDataSet.Tables(0).Rows.Count - 1
        intTotalCPO += Cutco_testDataSet.Tables(0).Rows(i).Item("CPO")
        intTotalRecs += Cutco_testDataSet.Tables(0).Rows(i).Item("Rec's")
    Next
    lblTotalCpo.Text = intTotalCPO.ToString("c0")
    lblTotalRecs.Text = intTotalRecs.ToString()

另外,当值为null时,我遇到了问题,它告诉我它无法添加DBNull。如果值还没有输入(null),计数器是否会继续并忽略,或者只将null计数为0。

提前谢谢!

1 回复 | 直到 5 年前

Saurabh 12 年前

我正在重写您的代码:

'Dim row As Cutco_testDataSet.DemosRow

'Dim intTotalItems As Integer
'For Each row In Cutco_testDataSet.Demos.Rows
'    intTotalItems += 1
'Next
'No need to use above "for loop" for counting total rows.  
lblTotalItems.Text = Cutco_testDataSet.Demos.Rows.Count

'Declare the variables for the values to be stored and later displayed
Dim intTotalCPO As Integer
Dim intTotalRecs As Integer
dim intTotdemosgiven as Integer

'to look in Demosdgv and add the corresponding data
'For i As Integer = 0 To Cutco_testDataSet.Tables(0).Rows.Count - 1
For Each row as Datarow in Cutco_testDataSet.Tables(0).Rows
    intTotalCPO += NullToZero(row("CPO"))
    intTotalRecs += NullToZero(row("Rec's"))

    intTotdemosgiven = intTotdemosgiven + IIf(UCase(nulltostring(row("DemosGiven"))) = "YES", 1, 0) 'I dont know exact field name for Demos given. 

Next
lblTotalCpo.Text = intTotalCPO.ToString("c0")
lblTotalRecs.Text = intTotalRecs.ToString()



Public Function NullToZero(ByRef FieldVal) As Double
'This function converts null or blank values to zero.
    If FieldVal Is Nothing OrElse FieldVal.ToString() = vbNullString Then
        Return 0
    Else
        Return FieldVal
    End If
End Function

Public Function NullToString(ByRef FieldVal) As String
    If FieldVal Is Nothing OrElse IsDBNull(FieldVal) Then
        Return vbNullString
    Else
        Return FieldVal
    End If
End Function

希望这能有所帮助