Three major categories
It is divided into two major categories:
Basic data type & reference type
Basic data type---value type---integral type---commonly used integers: Int, long integer: Long, small integer: Byle, medium integer short
--floating point--small floating point: float, medium floating point: Double large floating point: Declaml
--Boolean--bool (wrong type)--ture| | False
--Character Type-char (single character)
Reference types--strings--string
--Time Date--DateTime
Array
Type must be specified and length must be specified
Int[] A = new int[Tim length];
Int[] B = new int[]{add number};
String[] D = new string[]{"Double quotes with numbers, separated by commas, and a double quote can only be counted as one"};
Of course, not only the int type can be, other can also
Array traversal
Console.WriteLine (add index value inside b[]);
Console.read ();
foreach (int c in b) {
Console.WriteLine (c);
Array sorting
}
Array Assignment
a[index value] = number (because it is of type int);
Two-dimensional arrays
int[,] e = new int[1,1];
int[,] e1 = new int[,]{{},{},{}};
Two-dimensional array values
Console.WriteLine (e1[0,2])//Take two values from the 0th one
Bubble sort
int[] A =New int[] {9,5,8,4,2,1 }; for(inti =0; I < a.length-1; i++) { for(intIB = i +1; IB < A.length; ib++) { if(A[i] >A[ib]) { inth =A[i]; A[i]=A[ib]; A[IB]=h; } } } foreach(intKincha) {Console.WriteLine (k); } console.read ();
Collection
No need to specify type and length
Outside to add: using System.Collections;
ArrayList arr =NewArrayList (); DateTime DT=NewDateTime ( ., One,3);
Add arr. ADD ("ABC"); Arr. ADD (123); Arr. ADD (true); Arr. ADD (DT); //Collection Traversal//foreach (var x in arr)//{ //Console.WriteLine (x); //} //arr. Remove (123); //arr. RemoveAt (1); //arr. Reverse ();//Sequential RolloverArr. Insert (2,"AC"); Console.WriteLine (arr. Contains (123)); //foreach (var x in arr)//{ //Console.WriteLine (x); //}Console.read ();
Generic collection
Not specified length specified type
//class to be on the same lateral as the static void Main (string[] args)classuser{PUBILCintuser_id; PUBILCstringuser_name;}
New Linst<user> i =NewLinst<user>();
Insert User SJ=Newuser (); sj.user_id=1; Sj.user_name="Zhang San"; I.add (SJ); user LS=Newuser (); ls.user_id=2; Ls.user_name="John Doe"; I.add (LS);foreach(User Xinchi) {Console.WriteLine (x.user_id);}
list< type or class table name > i = new list< type or class's Table name > ();
Add to
I.add (e.g. 123);
Regular expressions
stringstr ="\""; stringtemp =Console.ReadLine (); Regex Rx=NewRegex ("\\d"); if(Rx. IsMatch (temp)) {Console.WriteLine ("non-negative integers"); }Else{Console.WriteLine ("is not"); }
Array
Try { intint. Parse (temp); Console.WriteLine (" is number "); } Catch { Console.WriteLine (" you are not entering a number "); } Console.WriteLine (x);
November 3, 2017 VS three broad classes & Arrays &VS& collections & Generic Collections