Override OnInit() event

On the code behind, use intelliSense to show available page's events to override.

Type the following to enable intelliSense;

protected override ....

you see on the image below that list of available events will show as you type. Select the event you want to override and it will auto fill-in the event format code.

After you select an event, code similar to image below (depending on the method you selected) will show. Enter the additional code after the baseOnInit(e);, as shown below. 

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