How to convert values in Datagridview from String to Double?

Ako Musha

7y8.2k

I have a calculated column in datagridview when I am trying to use the data from that column to calculate another parameter, I am getting an error as "Converting from string to Double is not valid"

How can I convert the values to double? Thanks so much for your help!

Here is what I was trying to do, but does not do anything!

Convert.ToDouble (Data1.Rows(i).Value.Cells(10).Value)

and also tryied this command as well, not working...

Dim S As Double = 0
Double.TryParse(Data1.Rows(i).Cells(10).Value, S)

2 Replies

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Suraj Kumar7y ago
Accepted answer
You need to write an event - rowdatabound of datagridview where you can write code for converting string values to double. Here you need to check that values before conversion.
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
double number;
        double output;

        //Checking the RowType of the Row
        if(e.Row.RowType==DataControlRowType.DataRow)
        {
          if (Double.TryParse(Convert.ToInt32(e.Row.Cells[10].Text, out number))
              output = Convert.ToDouble(Convert.ToInt32(e.Row.Cells[10].Text);
            else
               output = 0;
        }
    }
As string values like blank space and other values can not be converted into double so tryparese is used to check whether it can be converted or not.
You can also find textbox or any other control and their value Rowdatabound event of gridview.

Hope this will help you.
Ako Musha7y ago
thanks for the response. I calculated Cells(10) as follow (needed to calculate the sum of every 10 rows)....

For i = 0 To data1.Rows.Count - 1
sum += data1(0, i).Value
If i.ToString.EndsWith("9") Then
data1(10, i).Value = sum
sum = 0
End If
Next

now I have difficulty using this calculated "sum" vales in that cell for another calculation! is there any way that I can fix this to not get this error ("Converting from string to Double is not valid" ), any help would be appreciated. thanks.