第3章C# 语法基础

1、1郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 第第3章章 c# 语法基础语法基础 2郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int i1 = -10; uint i2 = 10; long l1 = -1000; ulong l2 = 1000; short s1 = -300; ushort s2 = 300; sbyte b1 = -5; sbyte b2 = 0; 3郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 char ch1 = a; char ch2 = ; char ch1 = abc; char ch2 = ; 4郑宇军郑宇军 人民邮电出版社人民

2、邮电出版社 2009 double x = 1.2; float y = 0.5f; decimal z = 3.2m; 5郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 bool b1 = true; bool b2 = false; 6郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 struct complexnumber public double a; public double b; complexnumber c1; c1.a = 2.5; c1.b = 5; 7郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 enum weekday mon, tues, wed

3、n, thur, fri, sat, sun weekday day1 = weekday.mon; 8郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 class complexnumber public double a; public double b; complexnumber c1 = new complexnumber(); c1.a = 2.5; c1.b = 5; 9郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 class complexnumber public double a; public double b; complexnumber c1 = new

4、complexnumber(); c1.a = 2.5; c1.b = 5; c1 a: 2.5 b: 5 10郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 class complexnumber public double a; public double b; complexnumber c1 = new complexnumber(); c1.a = 2.5; c1.b = 5; complexnumber c2 = c1; c1 a: 2.5 b: 5 c2 11郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 class complexnumber public doub

5、le a; public double b; complexnumber c1 = new complexnumber(); c1.a = 2.5; c1.b = 5; complexnumber c2 = c1; c2.b = 10; c1 a: 2.5 b: 10 c2 12郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 struct complexnumber public double a; public double b; complexnumber c1 = new complexnumber(); c1.a = 2.5; c1.b = 5; c1 a: 2.5 b: 5 1

6、3郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 struct complexnumber public double a; public double b; complexnumber c1 = new complexnumber(); c1.a = 2.5; c1.b = 5; complexnumber c2 = c1; c1 a: 2.5 b: 5 c2 a: 2.5 b: 5 14郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 struct complexnumber public double a; public double b; complexnumber c1 =

7、 new complexnumber(); c1.a = 2.5; c1.b = 5; complexnumber c2 = c1; c2.b = 10; c1 a: 2.5 b: 5 c2 a: 2.5 b: 10 15郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int nums = new int3; nums0 = 3; nums1 = 6; nums2 = 9; int nums = 3,6,9; 16郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int, x = new int3,2; x0,0 = 1; x0,1 = 2; x1,0 = 3; x2,0 = 6;

8、int, x = 1,2, 3,5, 6,9; 17郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 值类型值类型 int a = 100; long b = a; float x = 0.5f; double y = x; long a = 100; int b = (int)a; double x = 0.5; float y = (float)x; 18郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 值类型值类型 class student class graduate : student graduate g1 = new graduate(); student s1 = g

9、1; graduate g2 = (graduate)s1; 引用类型引用类型 19郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 值类型值类型 int x = 3; object y = x; int z = (int)y; 引用类型引用类型 20郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int x = 2*4; int y = x+1; int z = 6 - y/3; 21郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int x = 2*4; int y = x+; y+; x-; 22郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 byte x = 20

10、; byte y = x; x = (x 2); byte z = x 23郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 byte x = 20; x = y); 25郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int x = 15; int y = 15 /2 * 2; bool b1 = (x y) bool b2 = (x y) | (y y) ? x : y; 27郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 if(x = 60) console.write(及格及格); console.write(及格及格); x=60 结束结束 开始开始 28郑宇军郑宇军

11、 人民邮电出版社人民邮电出版社 2009 if(x = 60) console.write(及格及格); else console.write(不及格不及格); console.write(及格及格); x=60 结束结束 开始开始 console.write(不及格不及格); 29郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 char grade; if(x = 80) grade = 优优; else if (x=60) grade = 良良 else grade = 差差; grade = 优优 x=80 结束结束 开始开始 grade = 良良grade = 差差 x=60 3

12、0郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int i = x / 20; char grade; switch(i) case 4: grade = 优优; break; case 3: grade = 良良; break; default: grade = 差差; break; grade = 优优 i=4 结束结束 开始开始 grade = 良良grade = 差差 i=3 31郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 double x = 1000; int i = 0; while(i 5) x = x * 1.1; i+; x = x * 1.1; i+;

13、i5 结束结束 开始开始 x=1000; i=0; 32郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 double x = 1000; int i = 0; do x = x * 1.1; i+; while(i 5) x = x * 1.1; i+; i5 结束结束 开始开始 x=1000; i=0; 33郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 double x = 1000; for(int i = 0; i 5; i+) x = x * 1.1; x = x * 1.1; i+; i5 结束结束 开始开始 x=1000; i=0; 34郑宇军郑宇军 人民邮电出版社人民邮电出版社 2009 int x = 3,7