Phone Number validation in asp.net

Question

Hi I have two tables users and vendors and user have mobile no field vendor_contact and user also have mobile no field user_contact . Now while inserting contact no in user or vendor i want to check weather that contact no is exist in both tables or not.... i don't have any common field in both tables. How i ll do this?

Sanjeeb Lenka · Answer

hi In the textbox textchanged event check the contactno in database. if found then show a msg. if not then allow the no. you can use this query to get the contact no from both the tables. SELECT e.contact FROM (SELECT vendor_contact as contact FROM vendors UNION SELECT user_contact as contact FROM users) AS e where e.contact='7842392529' in above query i use contact no datatype as varchar. if you used bigint then remove the double coat.

Kiran Kumar Talikoti · Answer

Hi Rachayita May be this will work for youdo check not sure var query=from c in DB.Users from d in DB.Vendors where c.Moble_No==d.Mobile_no select new { }; if(query!=null) { messagebox.show(Contact Exist); } else { //logic for accepting mobile_no }