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<h1>Grid Cells Editing Confirm Tullio</h1>
We implement the 'onCellUpdate' Grid function. When a cell value is edited, 'onCellUpdate' is called. That callback can be used for Client-Server validation of the Cell Editing. The function is implemented for the 'Quantity' column and we simulate Ajax call to a Web Server by using setTimeout and
confirm the changes by calling the 4th argument of 'onCellUpdate', which is a function. When we call it with 'true', changes are confirmed. Otherwise, they are canceled. In this example, when the 'Quantity' is > 10, changes are confirmed.
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