Question

I encountered a problem where when the user select the id from the data grid view and click the ‘delete’ button, A error prompts us like this: “Input string was not in the correct format”.

Here are the codes to make you guys have better understanding of the codes.

private void btnDel_Click(object sender, EventArgs e)
    {
        using (satsEntities Setupctx = new satsEntities())
        {
            int ID = Int32.Parse(lblID.Text);
            var DeleteSL = (from delLS in Setupctx.locationstations
                           where delLS.locationstationID == ID
                           select delLS).Single();
            Setupctx.DeleteObject(DeleteSL);
            Setupctx.SaveChanges();
            this.Delete_LS_Load(null, EventArgs.Empty);
            MessageBox.Show("Selected Location Station Has Been Deleted.");
        }
    }

Answer 1

You are getting this exception “Input string was not in a correct format.” on

int ID = Int32.Parse(lblID.Text);

Your lblID.Text holds some thing which can’t be converted to a number. May be something that contains characters along with numbers.

Try using int.TryParse to see if you can convert the text to number.

int ID;
if(!int.TryParse(lblID.Text, out ID))
{
   Console.WriteLine("Invalid Number in lblID.Text");
}