I have an WPF form with 3 textbox named FirstName LastName and GPA, and i want to check their content before inserting into the database. But i am trying to do this in another class. How can i make to access the textbox control from my class? the WPF window is named AddStudent and the class i want to make the check is named Consiste. I made Consiste static so i can use it on my AddStudent without creating an instance.