下面是比较运算符的示例。
范例1:
<
script>
function gfg() {
let val1 = 5;
// Equality Operators
document.write(val1 == 5);
document.write( "<
br>
" );
// Relational Operators
document.write(val1 >
0);
}
gfg();
<
/script>
输出如下:
true
true
操作符用于对操作数执行特定的数学和逻辑计算。像C, C ++, Java, Python和其他各种语言一样, JavaScript也支持比较方式操作。比较运算符在逻辑语句中用于确定变量或值之间的相等性或差异。 JavaScript支持各种比较运算符:
- 平等经营者
- 关系运算符
平等(==):该运算符用于比较两个操作数的相等性。如果相等, 则条件为true, 否则为false。
语法如下:
x == y
以下示例说明了(==)JavaScript中的运算符:
范例1:
<
script>
// Illustration of (==) operator
let val1 = 5;
let val2 = '5' ;
// Checking of operands
console.log(val1 == 5);
console.log(val2 == 5);
console.log(val1 == val1);
// Check against null and boolean value
console.log(0 == false );
console.log(0 == null );
<
/script>
输出如下:
>
true
>
true
>
true
>
true
>
false
范例2:
<
script>
// Illustration of (==) operator
let obj1 = { 'val1' : 'value' };
let obj2 = { 'val2' : 'value' };
// Checking of operands
console.log(obj1.val1 == 'value' );
console.log(obj1 == obj2);
console.log(obj1.val1 == obj2.val2);
// Check against undefined
console.log(0 == undefined);
console.log( null == undefined);
<
/script>
输出如下:
>
true
>
false
>
true
>
false
>
true
一世平等(!=):该运算符用于应对两个操作数的不等式。如果相等, 则条件为假, 否则为真。
语法如下:
x != y
以下示例说明了(!=)操作符inJavaScript:
范例1:
<
script>
// Illustration of (!=) operator
let val1 = 5;
let val2 = '5' ;
// Checking of operands
console.log(val1 != 6);
console.log(val2 != '5' );
console.log(val1 != val1);
// Check against null and boolean value
console.log(0 != false );
console.log(0 != null );
<
/script>
输出如下:
>
true
>
false
>
false
>
false
>
true
范例2:
<
script>
// Illustration of (!=) operator
let obj1 = { 'val1' : 'value' };
let obj2 = { 'val2' : 'value' };
// Checking of operands
console.log(obj1.val1 != 'value' );
console.log(obj1 != obj2);
console.log(obj1.val1 != obj2.val2);
// Check against undefined
console.log(0 != undefined);
console.log( null != undefined);
<
/script>
输出如下:
>
false
>
true
>
false
>
true
>
false
严格平等(===):该运算符用于要求两个操作数的类型相等。如果值和类型都相等, 则条件为true, 否则为false。
语法如下:
x === y
以下示例说明了(===)操作符inJavaScript:
范例1:
<
script>
// Illustration of (===) operator
let val1 = 5;
let val2 = '5' ;
// Checking of operands
console.log(val1 === 6);
console.log(val2 === '5' );
console.log(val1 === val1);
// Check against null and boolean value
console.log(0 === false );
console.log(0 === null );
<
/script>
输出如下:
>
false
>
true
>
true
>
false
>
false
范例2:
<
script>
// Illustration of (===) operator
let obj1 = { 'val1' : 'value' };
let obj2 = { 'val2' : 'value' };
// Checking of operands
console.log(obj1.val1 === 'value' );
console.log(obj1 === obj2);
console.log(obj1.val1 === obj2.val2);
// Check against undefined
console.log(0 === undefined);
console.log( null === undefined);
<
/script>
输出如下:
>
true
>
false
>
true
>
false
>
false
严格的平等(!==):该运算符用于ompare两个具有类型的操作数的不等式。如果值和类型都不相等, 则条件为true, 否则为false。
语法如下:
x !== y
以下示例说明了(!==)操作符inJavaScript:
范例1:
<
script>
// Illustration of (!==) operator
let val1 = 5;
let val2 = '5' ;
// Checking of operands
console.log(val1 !== 6);
console.log(val2 !== '5' );
console.log(val1 !== val1);
// Check against null and boolean value
console.log(0 !== false );
console.log(0 !== null );
<
/script>
输出如下:
>
true
>
false
>
false
>
true
>
true
范例2:
<
script>
// Illustration of (!==) operator
let obj1 = { 'val1' : 'value' };
let obj2 = { 'val2' : 'value' };
// Checking of operands
console.log(obj1.val1 !== 'value' );
console.log(obj1 !== obj2);
console.log(obj1.val1 !== obj2.val2);
// Check against undefined
console.log(0 !== undefined);
console.log( null !== undefined);
<
/script>
输出如下:
>
false
>
true
>
false
>
true
>
true
关系运算符G胜于运算符(> ):这个运算符习惯于检查左侧值是否大于右侧值。如果值较大, 则条件为true, 否则为false。
语法如下:
x >
y
以下示例说明了(> )操作符inJavaScript:
范例1:
<
script>
// Illustration of (>
) operator
let val1 = 5;
let val2 = "5" ;
// Checking of operands
console.log(val1 >
0);
console.log(val2 >
"10" );
console.log(val1 >
"10" );
console.log(val2 >
0);
<
/script>
输出如下:
>
true
>
true
>
false
>
true
范例2:
<
script>
// Illustration of (>
) operator
let obj1 = { 'val1' : 1};
let obj2 = { 'val2' : 3};
// Checking of operands
console.log(obj1.val1 >
0);
console.log(obj1 >
obj2);
console.log(obj1.val1 >
obj2.val2);
console.log(obj2 >
obj1);
console.log(obj2.val2 >
obj1.val1);
<
/script>
输出如下:
>
true
>
false
>
false
>
false
>
true
G大于或等于运算符(> =):这个运算符习惯于检查左侧操作数是否大于或等于右侧操作数。如果值是g大于或等于那么条件为真, 否则为假。
语法如下:
x >
= y
以下示例说明了(> =)操作符inJavaScript:
范例1:
<
script>
// Illustration of (>
=) operator
let val1 = 5;
let val2 = "5" ;
// Checking of operands
console.log(val1 >
= 5);
console.log(val2 >
= "15" );
console.log(val1 >
= "5" );
console.log(val2 >
= 15);
<
/script>
输出如下:
>
true
>
true
>
true
>
false
范例2:
<
script>
// Illustration of (>
=) operator
let obj1 = { 'val1' : 1};
let obj2 = { 'val2' : 3};
// Checking of operands
console.log(obj1.val1 >
= 0);
console.log(obj1 >
= obj2);
console.log(obj1.val1 >
= obj2.val2);
console.log(obj2 >
= obj1);
console.log(obj2.val2 >
= obj1.val1);
<
/script>
输出如下:
>
true
>
true
>
false
>
true
>
true
大号比操作员重要(< ):这个运算符习惯于检查左侧值是否小于右侧值。如果是, 则条件为真, 否则为假。
语法如下:
x <
y
以下示例说明了(< )操作符inJavaScript:
范例1:
<
script>
// Illustration of (<
) operator
let val1 = 5;
let val2 = "5" ;
// Checking of operands
console.log(val1 <
15);
console.log(val2 <
"0" );
console.log(val1 <
"0" );
console.log(val2 <
15);
<
/script>
输出如下:
>
true
>
false
>
false
>
true
范例2:
<
script>
// Illustration of (<
) operator
let obj1 = { 'val1' : 1};
let obj2 = { 'val2' : 3};
// Checking of operands
console.log(obj1.val1 <
10);
console.log(obj1 <
obj2);
console.log(obj1.val1 <
obj2.val2);
console.log(obj2 <
obj1);
console.log(obj2.val2 <
obj1.val1);
<
/script>
输出如下:
>
true
>
false
>
true
>
false
>
false
大号等于或小于等于运算符(< =):该运算符用于检查左侧操作数的值是否小于或等于右侧操作数的值。如果是, 则条件为真, 否则为假。
语法如下:
x <
= y
以下示例说明了(< =)操作符inJavaScript:
范例1:
<
script>
// Illustration of (<
=) operator
let val1 = 5;
let val2 = "5" ;
// Checking of operands
console.log(val1 <
= 15);
console.log(val2 <
= "0" );
console.log(val1 <
= "0" );
console.log(val2 <
= 15);
<
/script>
输出如下:
>
true
>
false
>
false
>
true
范例2:
<
script>
// Illustration of (<
=) operator
let obj1 = { 'val1' : 1};
let obj2 = { 'val2' : 3};
// Checking of operands
console.log(obj1.val1 <
= 10);
console.log(obj1 <
= obj2);
console.log(obj1.val1 <
= obj2.val2);
console.log(obj2 <
= obj1);
console.log(obj2.val2 <
= obj1.val1);
<
/script>
输出如下:
>
true
>
true
>
true
>
true
>
false
【JavaScript比较运算符用法和介绍指南】支持的浏览器:所有人都支持的浏览器JavaScript比较运算符下面列出:
- 谷歌浏览器
- 火狐浏览器
- 歌剧
- 苹果浏览器
- Edge
- IE浏览器
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