تقدم عملگر ترتيب انجام عمليات را دريك عبارت محاسباتي مشخص ميكند.
عملگرهاي ضرب(*)وتقسيم(/) اولويت بيشتري نسبت به جمع وتفريق(+ , -) دارند .
مثال ـ مشابه رياضي سنتي اول ضرب انجام ميشود.
let x = 100 + 50 * 3;
هنگام استفاده از پرانتز ابتدا، اعمال داخل پرانتز انجام ميگيرد.
مثال ـ عبارت با پرانتز
let x = (100 + 50) * 3;
عمليات با اولويت يكسان مثل(* , /) از چپ براست انجام ميشود.
مثال ـ اول تقسيم وبعد عمل ضرب
let x = 100 / 50 * 3;
در جدول زير عملگرها و عدد اولويت آنها همراه مثالي آمده است.
Operator Precedence ValuesExpressions in parentheses are computed before the rest of the expressionFunction are executed before the result is used in the rest of the expression |
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Val | Operator | Description | Example |
18 | ( ) | Expression Grouping | (100 + 50) * 3 |
17 | . | Member Of | person.name |
17 | [] | Member Of | person["name"] |
17 | ?. | Optional Chaining ES2020 | x ?. y |
17 | () | Function Call | myFunction() |
17 | new | New with Arguments | new Date("June 5,2022") |
16 | new | New without Arguments | new Date() |
Increment Operators Postfix increments are executed before prefix increments |
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15 | ++ | Postfix Increment | i++ |
15 | -- | Postfix Decrement | i-- |
14 | ++ | Prefix Increment | ++i |
14 | -- | Prefix Decrement | --i |
NOT Operators | |||
14 | ! | Logical NOT | !(x==y) |
14 | ~ | Bitwise NOT | ~x |
Unary Operators | |||
14 | + | Unary Plus | +x |
14 | - | Unary Minus | -x |
14 | typeof | Data Type | typeof x |
14 | void | Evaluate Void | void(0) |
14 | delete | Property Delete | delete myCar.color |
Arithmetic Operators Exponentiations are executed before multiplications Multiplications and divisions are executed before additions and subtractions |
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13 | ** | Exponentiation ES2016 | 10 ** 2 |
12 | * | Multiplication | 10 * 5 |
12 | / | Division | 10 / 5 |
12 | % | Division Remainder | 10 % 5 |
11 | + | Addition | 10 + 5 |
11 | - | Subtraction | 10 - 5 |
11 | + | Concatenation | "John" + "Doe" |
Shift Operators | |||
10 | << | Shift Left | x << 2 |
10 | >> | Shift Right (signed) | x >> 2 |
10 | >>> | Shift Right (unsigned) | x >>> 2 |
Relational Operators | |||
9 | in | Property in Object | "PI" in Math |
9 | instanceof | Instance of Object | x instanceof Array |
Comparison Operators | |||
9 | < | Less than | x < y |
9 | <= | Less than or equal | x <= y |
9 | > | Greater than | x > y |
9 | >= | Greater than or equal | x >= Array |
8 | == | Equal | x == y |
8 | === | Strict equal | x === y |
8 | != | Unequal | x != y |
8 | !== | Strict unequal | x !== y |
Bitwise Operators | |||
7 | & | Bitwise AND | x & y |
6 | ^ | Bitwise XOR | x ^ y |
5 | | | Bitwise OR | x | y |
Logical Operators | |||
4 | && | Logical AND | x && y |
3 | || | Logical OR | x || y |
3 | ?? | Nullish Coalescing ES2020 | x ?? y |
Conditional (ternary) Operator | |||
2 | ? : | Condition | ? "yes" : "no" |
Assignment Operators Assignments are executed after other operations |
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2 | = | Simple Assignment | x = y |
2 | : | Colon Assignment | x: 5 |
2 | += | Addition Assignment | x += y |
2 | -= | Subtraction Assignment | x -= y |
2 | *= | Multiplication Assignment | x *= y |
2 | **= | Exponentiation Assignment | x **= y |
2 | /= | Division Assignment | x /= y |
2 | %= | Remainder Assignment | x %= y |
2 | <<= | Left Shift Assignment | x <<= y |
2 | >>= | Right Shift Assignment | x >>= y |
2 | >>>= | Unsigned Right Shift | x >>>= y |
2 | &= | Bitwise AND Assignment | x &= y |
2 | |= | Bitwise OR Assignment | x |= y |
2 | ^= | Bitwise XOR Assignment | x ^= y |
2 | &&= | Logical AND Assignment | x &&= y |
2 | ||= | Logical OR Assignment | x ||= y |
2 | => | Arrow | x => y |
2 | yield | Pause / Resume | yield x |
2 | yield* | Delegate | yield* x |
2 | ... | Spread | ... x |
1 | , | Comma | x , y |