Objective-C 关系运算符

下表显示了 Objective-C 语言支持的所有关系运算符。假设变量 A 为 10，变量 B 为 20，则

运算符	描述	实例
==	检查两个操作数的值是否相等；如果是，则条件变为 true。	(A == B) 不为 true。
!=	检查两个操作数的值是否相等；如果值不相等，则条件变为 true。	(A != B) 为 true。
>	检查左操作数的值是否大于右操作数的值；如果是，则条件变为 true。	(A > B) 不为 true。
<	检查左操作数的值是否小于右操作数的值；如果是，则条件变为 true。	(A < B) 为 true。
>=	检查左操作数的值是否大于或等于右操作数的值；如果是，则条件变为 true。	(A >= B) 不为 true。
<=	检查左操作数的值是否小于或等于右操作数的值；如果是，则条件变为 true。	(A <= B) 为 true。

实例

尝试以下实例来理解 Objective-C 编程语言中可用的所有关系运算符:

#import <Foundation/Foundation.h>
int main() {
  int a = 21;
  int b = 10;
  if( a == b ) {
   NSLog(@"Line 1 - a is equal to b\n" );
  } else {
   NSLog(@"Line 1 - a is not equal to b\n" );
  }
  if ( a < b ) {
   NSLog(@"Line 2 - a is less than b\n" );
  } else {
   NSLog(@"Line 2 - a is not less than b\n" );
  }
  if ( a > b ) {
   NSLog(@"Line 3 - a is greater than b\n" );
  } else {
   NSLog(@"Line 3 - a is not greater than b\n" );
  }
  /* Lets change value of a and b */
  a = 5;
  b = 20;
  if ( a <= b ) {
   NSLog(@"Line 4 - a is either less than or equal to b\n" );
  }
  if ( b >= a ) {
   NSLog(@"Line 5 - b is either greater than or equal to b\n" );
  }
}

运行一下

结果如下:

2022-07-07 22:42:18.254 demo[9486] Line 1 - a is not equal to b
2022-07-07 22:42:18.254 demo[9486] Line 2 - a is not less than b
2022-07-07 22:42:18.254 demo[9486] Line 3 - a is greater than b
2022-07-07 22:42:18.254 demo[9486] Line 4 - a is either less than or equal to b
2022-07-07 22:42:18.254 demo[9486] Line 5 - b is either greater than or equal to b

Objective-C 关系运算符

实例

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