In addition to deleting a GridView's underlying data, another common need is to allow end users to edit the data displayed in a GridView. With ASP.NET 1.x's DataGrid control, editing the data is certainly possible, but requires creating three event handlers and writing a dozen or so lines of code. With the GridView and ASP.NET 2.0, it is possible to create an editable GridView without writing a single line of code! All of the necessary functionality is encapsulated within the GridView.
The GridView allows editing on a row-by-row basis. An editable GridView contains an additional column with an Edit button in each row. When the end user clicks on an Edit button that row becomes editable, causing the Edit button to change to Update and Cancel buttons and the other columns to become TextBoxes. The end user can then update one or more column values and click Update to save their changes.
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