Thank you Pavlina.
For the ones who need it, below the code in C# :
GridEditableItem editItem = (GridEditableItem)e.Item;
TextBox txtDescription = (TextBox)editItem["Description"].Controls[0];
txtDescription.Width = Unit.Percentage(80);
Thank you Pavlina.
For the ones who need it, below the code in C# :
GridEditableItem editItem = (GridEditableItem)e.Item;
TextBox txtDescription = (TextBox)editItem["Description"].Controls[0];
txtDescription.Width = Unit.Percentage(80);