InfoPath Dev

I create the new list form template when user submit the form that time i want to submit this form to my exiting SharePoint list form.

I want to perform Search functionality.In my drop Down list box contains no of item i want to give search functionality for that user can enter some value if that value is contains in dropdown i want to set drop down value.

I create the List form Template in infopath I add on drop down list box in that list box there is thousands of item i want to give search functionality to user user can enter the Name into textbox and if this record is exit that tine automatically select into dropdown list box.

Hey I create offline mode List Form Template I want to user only submit form only once.When user comes to online form will be submitted only once. Currently when user modify this old form then user can submit this form as new form i don't want to do this. Is any solution ?

Ok thanks i try this.

I want to show external List data in my List form so how can i achieve this?

I want to change the label when user open online.

I create List form Template i want to add External Data Picker but this control not showing for List Form Template is any one know why?