JavaFX Script Programming Language 学习 No.6

 第六课　运算符

 

一、赋值运算符 =

示例代码1：

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result = num1 + num2;
days = ["Mon","Tue","Wed","Thu","Fri"];

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二、算术运算符 +-*/

+ (additive operator) - (subtraction operator) * (multiplication operator) / (division operator) mod (remainder operator) 示例代码2： var result = 1 + 2; // result is now 3 println(result); result = result - 1; // result is now 2 println(result); result = result * 2; // result is now 4 println(result); result = result / 2; // result is now 2 println(result); result = result + 8; // result is now 10 println(result); result = result mod 7; // result is now 3 println(result); 也可以缩写运算符 +=  -=  *=  /= 示例代码3： var result = 0; result += 1; println(result); // result is now 1 result -= 1; println(result); // result is now 0 result = 2; result *= 5; // result is now 10 println(result); result /= 2; // result is now 5 println(result);

一元运算符

- 	Unary minus operator; negates a number
++  	Increment operator; increments a value by 1
--    	Decrement operator; decrements a value by 1
not   	Logical complement operator; inverts the value of a boolean

示例代码4:
 
 

var result = 1; // result is now 1

result--;  // result is now 0
println(result);

result++; // result is now 1
println(result);

result = -result; // result is now -1
println(result);

var success = false;
println(success); // false
println(not success); // true

 
 

自增自减运算符

示例代码5:

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var result = 3;
result++;
println(result); // result is now 4
++result;
println(result); // result is now 5
println(++result); // result is now 6
println(result++); // this still prints 6!
println(result); // but the result is now 7

 

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 关系运算符

==	等于
!=	不等于
>	大于
>=	大于等于
<	小于
<=	小于等于

示例代码6:

def num1 = 1;
def num2 = 2;

println(num1 == num2); // prints false
println(num1 != num2); // prints true
println(num1 > num2);  // prints false
println(num1 >= num2); // prints false
println(num1 < num2);  // prints true
println(num1 <= num2); // prints true

 

条件运算符

and

or

 

示例代码7:

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def username = "foo";
def password = "bar";

if ((username == "foo") and (password == "bar")) {
     println("Test 1: username AND password are correct");
}

if ((username == "") and (password == "bar")) {
     println("Test 2: username AND password is correct");
}

if ((username == "foo") or (password == "bar")) {
     println("Test 3: username OR password is correct");
}

if ((username == "") or (password == "bar")) {
     println("Test 4: username OR password is correct");
}

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输出：

Test 1: username AND password are correct
Test 3: username OR password is correct
Test 4: username OR password is correct

 

类型比较运算符

instanceof

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def str1="Hello";
println(str1 instanceof String);  // prints true

def num = 1031;
println(num instanceof java.lang.Integer); // prints true

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