小编pyt*_*hon的帖子

我真正的应用程序问题看起来如下所示

Employee empl = new Employee(397947, "David", "Redson", 80000);
        employees.Add(empl);
        employees.Add(new Employee(174966, "Alfred", "Swanson", 50000));
        employees.Add(new Employee(848024, "Alima", "Bieyrou", 40000));
        employees.Add(new Employee(number: 397462, fName: "Robert",
                                     lName: "Nants", salary: 30000));


string s = employees.Where(a => a.EmployeeNumber == 20000).FirstOrDefault().FirstName;

当我使用FirstOrDefault时,它在没有匹配记录时抛出错误.如果有匹配的记录,我想返回值,否则它可以为null或空.