SSRS SELECT ALL emulation in ASP.NET Dropdown List

I have a multi-value parameter for SSRS report.

This parameter being a multi-select will have SELECT ALL option that selects all values under the drop down list. Challenge is emulating the same using ASP.NET drop down list as parameter source. I will use reportviewer control just to render and display report but not to show parameters. Parameters come from ASP.NET 开发者_开发问答page. How do I achieve SELECT ALL functionality in this case?

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You can achieve this in query to retrieve dummy record and do UNION. Just do a very simple thing showed below.

Select 0 as ID, "(Show All)" as Name
Union
Select Id, Name from MyTable

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You could use a jquery widget to do something like this. For example see Eric Hynds jQuery UI Mutliselect: http://www.erichynds.com/jquery/jquery-ui-multiselect-widget/

It has a 'select all' option