我想编写一个函数,可以在将值插入List之前完成一些检查.
例如:
例如:
class Person { public string Name { get; set; } public int Value { get; set; } public Guid Id { get; set; } } ------- var persons = new List<Person>(); // add a new person if John doesn't exist persons.AddIf(s => !s.Name.Equals("John"),new Person { ... }); ---- public static void AddIf(this List<T> lst,Func<T,bool> check,T data) { // how can I use the Func 'check' to check if exist an object with the // information that the client wrote and,if not exists,insert the new value // into the list??? if ( check ) }
如何使用Func’check’检查是否存在具有客户端写入信息的对象,如果不存在,则将新值插入列表中?