C # syntax exercises (3): Operators

Basic:. () [] x ++ X -- new typeof checked unchecked->: One Dollar: + -! ~ + + X -- x (t) x True False & sizeof multiplication and division: */% addition and subtraction: +-shift:> relation: = is as equal: =! = Logic: & ^ | condition: & | Value assignment: = + =-= * =/= % = & = | = ^ => = select :? :?? Others: =>

  
 

Integer/Integer = integer

Using system; Class myclass {static void main () {double D; D = 14/4; console. writeline (d); // 3 D = 14/4 .0; console. writeline (d); // 3.5 d = 14.0/4.0; console. writeline (d); // 3.5 d = 14.0/4; console. writeline (d); /// 3.5 console. writeline (); float F; F = 14/4; console. writeline (f); // 3 F = (float) (14.0/4.0);/* double is returned by default, so conversion */console is required. writeline (f); // 3.5 console. writeline (); int I; I = 14/4; console. writeline (I); // 3 I = (INT) (14.0/4.0); console. writeline (I); // 3 I = 14% 4; console. writeline (I); // 2 console. readkey ();}}

  
 

++ -- Double Type

Using system; Class myclass {static void main () {double f = 1.5; F ++; console. writeline (f); // 2.5 f --; console. writeline (f); // 1.5 console. writeline (++ F); // 2.5 console. writeline (-- F); // 1.5 console. readkey ();}}

  
 

? :

 
Using system; Class myclass {static void main () {int N, A = 11, B = 22; n = A> B? A: B; console. writeline (n); // 22 N =
 

??

 
Using system; Class myclass {static void main () {Int? X = NULL;/* specify NULL for the variable, which is generally used for values and Boolean types */INT y; y = x ?? -1;/* If X is null, the latter is returned. Otherwise, x */console. writeline (Y) is returned. //-1 x = 9; y = x ?? -1; console. writeline (y); // 9 console. readkey ();}}

  
 

=>

 
Using system; using system. LINQ; Class myclass {static void main () {int N1, N2; int [] NS = {22,333,444 4, 9}; n1 = NS. max (num => num); N2 = NS. min (num => num); console. writeline ("{0}, {1}", N1, N2); // 4444, 9 string [] Ss = {"AAA", "BBBB", "CCCCC ", "DD"}; n1 = ss. max (STR => Str. length); N2 = ss. min (STR => Str. length); console. writeline ("{0}, {1}", N1, N2); // 5, 2 console. readkey ();}}

  
 

& | ^!

Using system; Class myclass {static void main () {bool B; B = true & True; console. writeline (B); // true B = true & false; console. writeline (B); // false B = false & false; console. writeline (B); // false B = true | true; console. writeline (B); // true B = true | false; console. writeline (B); // true B = false | false; console. writeline (B); // false B = true ^ true; console. writeline (B); // false B = T Rue ^ false; console. writeline (B); // true B = false ^ false; console. writeline (B); // false B =! True; console. writeline (B); // false B =! False; console. writeline (B); // true console. readkey ();}}

  
 

& |; When determining conditions, try to use &, | instead of &, |; because the latter always has to calculate the result, it will be slow.

Using system; Class myclass {static void main () {bool B;/* In the first two cases, & no longer judge the value */B = false & true; console. writeline (B); // false B = false & false; console. writeline (B); // false B = true & True; console. writeline (B); // true B = true & false; console. writeline (B); // false/* In the first two cases | no longer judge the value */B = true | true; console. writeline (B); // true B = true | false; console. writeline (B); // true B = false | true; console. writeline (B); // true B = false | false; console. writeline (B); // false console. readkey ();}}