By default Visual Studio.NET initially displays Web pages  in a Design view. If your web page might be very heavy sometimes it might create lot of time to open the web form in designer mode to just change a simple tag.

You can define the settings on the visual studio to open the web form on  source view (asp.net tags) so that it will load the form faster and you can do the minor changes without going to the design mode. Advanced level asp.net developer may  not want to go the design view because they might find more easier to change any thing just from the source view.

Change default view in visual studio

If you prefer Source view, you can set it to be the default view.

a)    Go to Tools | Options… | HTML Designer and select Source View.

b)    Click OK button.

Same applies for WinForms if you are working on desktop application.

a)    Right-click on a WinForm in the Solution Explorer and then click Open With…. Open With dialog opens.

b)    Choose CSharp Editor in the list and then click Set as Default button.

c)    Click OK button.