Get Email address of all the cotacts
I am trying to get the email addresses of all the contacts available in the service cloud application.
The requirement is as follows:
1. Compare a given email address with all the email addresses.
2. If found, fetch the ID of that Contact.
3. Create a new record in Bill(Custom object) and set the ID of Contact to the above ID so that a parent-child relationship is created between the contact and bill.
I am using C# for this requirement. Please help me how to get all the email addresses from the application, compare it and fetch the id of the contact.