比較運算子

Java 入門

Jim White

Java Developer

比較

總是評估為 true 或 false（結果為 boolean）

將 age 與 minAge 比較

大於 >、小於 <

class GreaterThan {
  public static void main(String[] args){
    System.out.println(5 < 6); // Will print true, 5 is less than 6
  }
}

true

大於 >、小於 <

// Check if 5 is less than 6
boolean x = 5 < 6; // Value is true, because 5 < 6

// Check if 5 is greater than 6
boolean y = 5 > 6; // Value is false, 5 < 6

大於等於 >=

int minSpend = 25;
int total = 25;


// Check if total is greater or equal to minSpend
boolean freeDelivery = total >= minSpend; // Value is true, total is equal to minSpend

小於等於 <=

int minSpend = 25;
int total = 23;

// Check if total is less or equal to minSpend

boolean paidDelivery = total <= minSpend; // Value is true, total is less than minSpend

等於 ==

需要用 ==，= 是指定運算子

int userAccountNumber = 567346;
int submittedAccountNumber = 456777;

// Check if userAccountNumber is equal to submittedAccountNumber
boolean isUserAccountNumber = useraccountNumber == submittedAccountNumber;
// Value is false

不等於 !=

使用 !=

int userHealth = 235;

// Check whether userHealth is not zero
boolean alive = userHealth != 0; // Value is true, userHealth is not zero

比較總結

運算子	名稱	範例	範例結果
>	大於	6 > 6	`false`
<	小於	5 < 6	`true`
>=	大於等於	5 >= 6	`false`
<=	小於等於	5 <=6	`true`
==	等於	5 == 5	`true`
!=	不等於	5 != 5	`false`

所有運算的輸出都是 boolean

一起來練習吧！

Java 入門