Javascript with ASP.Net : Use Javascript to iterate through a gridview and find checkbox in each row

I was looking for a mechanism to iterate over a gridview using Javascript. I had to get the checkbox in each row and update that checkbox's checked status according to the corresponding header columns checkbox's status.

Just after googling a little bit , I found exactly what I was looking for. The following link has done the same thing. Have a look at this:

http://www.codeproject.com/KB/grid/GridCheckBox.aspx

** I believe when there are so many quality tutorials over the web, I do not really need to write one of my own unless the topic is something unique**

ASP.NET : How to use customvalidator with a file upload tool for client side validation

We really do not want to validate in the server side because it makes the server busy.
So a good approach is to validate in the client side using javascript. Here is a good tutorial that does it:

http://www.beansoftware.com/ASP.NET-FAQ/FileUpload-Validation.aspx

** I believe when there are so many quality tutorials over the web, I do not really need to write one of my own unless the topic is something unique**

Javascript: split method can be used to split based on string or regular expression.

If you want to split a string based on another string, this how you do it:
str.split(" ");

If you want to split a string based on a reges, this how you do it:
str.split(/\s/);

\s is a reges which is used for any space character like space,\n,\t or \r.