C # Indexer

1. The difference between an attribute and an index

   Property	Indexer
   Identify by name	Identifying with a parameter list
   Access by simple name	Access by [] operator
   Can be modified with static	cannot be modified with static
   Get accessor has no parameters	The get accessor has the same argument list as the index
   The set accessor contains an implicit value parameter	In addition to the value parameter, the index's set accessor has the same argument list as the index

3. Example

1 class Person2     {3         Private ReadOnly string[] _data =New string[6];4         Private ReadOnly string[] _keys = {5         "Name"," Age","Sex"6         };7 8         //Note: The program uses two methods to index:9         //one is an integer to subscript, and the other is the string (keyword name) as subscriptTen          Public string  This[intIDX] One         { A             Set -             { -                 if(IDX >=0&& IDX <_data. Length) the_DATA[IDX] =value; -             } -             Get -             { +                 if(IDX >=0&& IDX <_data. Length) -                     return_data[idx]; +                 return NULL; A             } at         } -          Public string  This[stringKey] -         { -             Set -             { -                 intIDX =FindKey (key); in                  This[IDX] =value; -             } to             Get +             { -                 return  This[FindKey (Key)]; the             } *         } $         Private intFindKey (stringkey)Panax Notoginseng         { -              for(inti =0; I < _keys. Length; i++) the                 if(_keys[i] = = key)returni; +             return-1; A         } the         Static voidMain (string[] args) +         { -Person record =NewPerson (); $record[0] ="Jhon Snow"; $record[1] =" at"; -record["Sex"] ="male"; -Console.WriteLine (record["Name"]); theConsole.WriteLine (record[" Age"]); -Console.WriteLine (record[2]);Wuyi console.readline (); the         } -}

C # Indexer