Collections and Arrays

Two-dimensional arrays:

One-dimensional array Beans

Two-dimensional array Form

Defined:

One-dimensional arrays:

Data type [] array variable name =new data type [ data length ];

Data type [] array variable name =new data type [ data length ]{1,2 , 3} ;

Two-dimensional arrays:

Array type [,] array variable = new data type [ number of rows, number of columns ];

int[,]a = new int [3,4];

Jagged arrays:

Data type [][]a = new data type [ number of rows ] []

Step two : define the decimal group

Data type []a1= new data type [ number of columns ]

Data type []a2= new data type [ number of columns ]

Step three: Put the decimal group in the Uncle Group

Collection

ArrayList a = new ArrayList ();

1. Add () append

1. Insert (,) inserts

   A.removeat () Delete the first few

   ArrayList linked list, no length limit, can add or remove elements at any time

   You need to precede the using System.Collections.

   Defined:

   ArrayList a = new ArrayList ();

   Operation:

1. Add ( data ) append

   A.insert ( index number , data ) Insert

   A.removeat ( index number ) Delete the first few

1. Count the number of elements in the collection.

   Value:

   a[ subscript ]

   Two:List definition:

   List < data type > A = new List < data type > ();

   List <int > A = new list <int > ();

   Operation:

   A.add ( data ) append

   A.insert ( index number , data ) Insert

   A.removeat ( index number ) Delete the first few

   A.count The number of elements in the collection.

1. Sort (); Sort Ascending

1. Revers (); reversal

   Three:dictionary<key,value> dictionary or hash table

   Defined:

   Dictionary<int,int> a = new Dictionary <int, int > ();

   Operation:

1. Add ( key value, data );

1. remove ( key value delete

    

   a.count   The number of elements in the collection.

    

   value: a[ Span style= "font-family: the song Body;" > key value

    

    

   stack< data type

    

1. Push ( value ); add

   Data type variable name = A.pop ();

   Queue: FIFO, cannot randomly take any of its values.

   Queue a <>a = new queue <> ();

1. Enqueue (); Add

   A.dequeue (); out

Collections and Arrays