hello

this is my first post in this forum and it has a small question

why do we get a doubled value when we calculate column in VB.net

i use this code

 
Dim i As Integer = 0
Dim total As Double
For i = 0 To ItemsDataGridView.RowCount - 1
total += ItemsDataGridView.Rows(i).Cells(3).Value
Next
TotalTextBox.Text = total

You mean the value is double what it should be or the data type is type double.

please check the attached pic.

it only counts one row and double it

Ok, I see what you mean. I believe you're having this problem because you have defined i as an integer variable set to zero at the top. When you created your For Next loop a new counter variable was set just for the counter. So you have two different i variables.



The i variable in ItemsDataGridView.Rows(i) is always set to zero because you defined it above as zero. Try removing the line



Dim i As Integer = 0, and lets see what happens.



Your code should be,



Dim total As Double



For i = 0 To ItemsDataGridView.RowCount - 1



total += ItemsDataGridView.Rows(i).Cells(3).Value



Next



TotalTextBox.Text = total

The same

By the way, the total text box is one of the database tables but when i add i new text box i don't have a problem it give me the right total for the column

Ok i found the error



I found a line in total text changed

It gives me the total



By the way, it woked even with

Dim i as intiger =0



Thank you for your help



But when i add a new invoice all old items shown for the new invoice