"
Error:Input string was not in a correct format.Couldn't store in Item_type_code
Column. Expected type is Int64.
I am unable to find exact problem.Please help m
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Because you are trying to store a string into a int field,
Convert.ToInt32(txtQty.Text);
Convert.ToInt32((string.IsNullOrEmpty(txtQty.Text) ? 0 : txtQty.Text));
Also you dont need to Convert.ToString on textbox.Text.