我怎么总从DataGridView vb.net总和

Question

，我要如何获得totalPrice的总和我的datagridview从MySQL

ProductName   Qty. Price totalPrice 
2 Pcs. Chickenjoy  5  59   295 
2 Pcs. Chickenjoy  1  69   69 
2 Pcs. Chickenjoy  1  69   59 

            TOTAL?? 

-the总和应该是423的问题是，这将增加一倍的总和

，尤其是圆形是我的代码：

Try 
    'declaring variable as integer to store the value of the total rows in the datagridview 

    Dim max As Integer = DataGridView1.Rows.Count - 1 
    Dim total As String = "Total ----------->" 
    'getting the values of a specific rows 


    For Each row As DataGridViewRow In DataGridView1.Rows 
     'formula for adding the values in the rows 
     DataGridView1.Rows(max).Cells(4).Value += row.Cells(4).Value 
     DataGridView1.Rows(max).Cells(3).Value = total 
    Next 
Catch ex As Exception 
    MsgBox(ex.Message) 
End Try 

截图 http://goo.gl/Ufj53b

Answer 1

您的主要问题似乎是使用For Each循环。当它到达最后一行时，它将累计总数加到它自己。 for循环只有第二个最后一行应该工作：

Try 
    'declaring variable as integer to store the value of the total rows in the datagridview 

    Dim max As Integer = DataGridView1.Rows.Count - 1 
    'getting the values of a specific rows 
    DataGridView1.Rows(max).Cells(3).Value = "Total ----------->" 

    For I = 0 To DataGridView1.Rows.Count - 2 
     'formula for adding the values in the rows 
     DataGridView1.Rows(max).Cells(4).Value += DataGridView1.Rows(I).Cells(4).Value 
    Next 
Catch ex As Exception 
    MsgBox(ex.Message) 
End Try 

Answer 2

试试这个：

Dim tot As Integer 
For Each row As DataGridViewRow In DataGridView1.Rows 
    'formula for adding the values in the rows 
    tot += row.Cells(4).Value 
Next 
DataGridView1.Rows(max).Cells(3).Value = total 
DataGridView1.Rows(max).Cells(4).Value = tot 

Answer 3

你的循环有错误。因为它会计算295,69和59的总和，然后再加上总和。这就是为什么它会加倍的总和。试试这个

Try 
    'declaring variable as integer to store the value of the total rows in the datagridview 

    Dim max As Integer = DataGridView1.Rows.Count - 1 
    Dim total As String = "Total ----------->" 
    Dim tot as integer =0 
    'getting the values of a specific rows 


    For Each row As DataGridViewRow In DataGridView1.Rows 
     'formula for adding the values in the rows 
     tot += row.Cells(4).Value 
    Next 
    DataGridView1.Rows(max).Cells(4).Value += tot 
     DataGridView1.Rows(max).Cells(3).Value = total 
Catch ex As Exception 
    MsgBox(ex.Message) 
End Try