Having a problem with inserting data into database

Question

HI there, i tried a lot but i think im missing something here and i really could not find out, for me it seems to be right.

when i run the program and fill the forms the i get an error on savechanges() method ... 

 

using (var db = new StudentEntities())

{

var add = new Book_Record

{

Book_Id = Int32.Parse(txtID.Text),

Book_Title = txtTitle.Text,

Book_Type = txtType.Text,

Book_Author = txtAuthor.Text,

Book_Edition = txtEdition.Text,

Book_IssuedBy = txtIssuedBy.Text,

Book_IssuedTo = txtIssuedTo.Text

};

db.Book_Record.Add(add);

db.SaveChanges();

}