To add the custom GridView control in your toolbox, follow
the subsequent steps:
Right click on the toolbox window then choose "Add Tab."
Type the name you want for the new tab, right click over it,
and click "Choose Items."
Click on the Browse button in the ".NET Framework
Components" tab, go to the custom GridView project, open the bin folder,
and choose MyCustomControl.dll.
The result is shown Figure 1.
Figure 1
Now drag the custom GridView control, go the properties
window, and check the IncludeColumnCheckBox property,
you will note that a new checkbox column has been added to the Gridview
automatically.
Figure 2
View the page in a browser, and click the checkbox element
in the GridView header row; you will note that all checkboxes are
checked/unchecked Client side without the need from you to write any bit of
code. And that is why Microsoft gives us the ability to create a new custom
control!
Figure 3