If you need to modify the behavior of standard web parts there are three options:
1. You only need to set the web part properties dynamically in your code
You need to create a user control, add the web part into it and write additional code. See chapter Setting web part properties dynamically in your code.
2. You need to modify the design (layout) of the web part
You need to use the custom web part layouts described in chapter Customizing web part layout.
3. You need to modify the code of the web part
You need to create a copy of the standard web part as described in chapter Modifying the code or design of standard web parts.
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