Asp. NET to generate background scripting problem solution

Asp.net| Background | script | solve | problem

Using ASP.net to develop Web applications often uses a pop-up dialog box, which I usually write.

Response.Write ("", "<script>alert") (' pop-up window! ');</script> ");

But the problem is that when the dialog box pops up, the whole page is white, and the progress bar is moving slowly, so you're OK after you click OK, why?

So I understand that the program is executed sequentially, when executed to the above statement, the program began to wait for the user's operation, and then down to execute, I did not notice at the beginning, but later the more ugly, how to think also have to change it over, let it pop up when the page still has content

Later, the teacher told me to use the following method can be

Page.registerstartupscript ("", "<script>alert") (' pop-up window! ');</script> ");

That's it!