I am not sure whether you are trying to get the control ID or the control type so you can see how to do both in Button1 Click event handler:
You know the control ID and want to find its type. You can see how you can get it and store it in the variable typeName. In our example it holds the type of the control with an ID "TextBox1".
You know the type of the control and you want to get its ID. We use the static method GetAllControlsOfType defined in the static class FindControls to get the controls with a specific type. In our case we use it to get all TextBox controls and store the collection in textBoxes. You can then iterate over this collection, access the ID property of each control of the specified type that it holds and apply your custom logic.
Regards,
Ivan Danchev
Telerik
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