Because the code is stored within the page or within a linked file, it is downloaded into the browser when a user accesses the page and, therefore, doesn't require a roundtrip to the server.
Say if u have a txt box labeled "txtuserid" and a label to display error "lbl Error" u can use the following function in java script to check the length and display error if the length is less than 12.
Here Mudassar Ahmed Khan has explained with an example, how to use Java Script with Check Box List in ASP. This article will explain how to validate Check Box List to check whether its items are selected or not and also how to get the Selected Items i.e. Now you can ask questions directly to me on my new site ASPForums.
Selected Text and Value of the Check Box List using Java Script in ASP. Here Mudassar Ahmed Khan has explained with an example, how to use Java Script with Radio Button List in ASP. This article will explain how to validate Radio Button List to find whether an item is selected or not and also how to get the Selected Text and Value of the Radio Button List using Java Script in ASP.
Either you add it directly to the Text Box on the aspx page.
But in that case Visual Studio will throws a warning though not an issue since Visual studio checks for Server Side events while onkeydown a client side event. Net Question Answer site, specially started to allow visitors of this site ask their doubts and queries. Just click the Ask Now button and ask your question now.