Hi,
i want to validate a form, and i want its function like twitter sign up form. Now if i use change event it trigger only after text filed value change and it losses focus, and if i use keyup event it will start validating as soon as he start filling the form.
Cann any one suggest best way of doing this and am using jquery
You might want to look at using a jQuery form validation plugin. I've had success with this one in the past.
use $('input').blur(callback);
This will make jquery validate the user input when the user leaves the field.
From experience, that's the only moment it is actually welcomed by the user. keyup is really annoying. For instance, it leads to interface telling the user he is wrong, when he only has just started typing. Pretty rude.
change() is good if your field has its value changed because of the user changing a value of another input, like in a multiple dropdown questionnaire.
What server-side language are you using?
If you're using ASP.NET then you can always drop on a field-validation control. Otherwise, .blur() as suggested by pixeline would be suitable.