TypeScript Operators

Operators are used to perform operations on program code, operating on one or more operands.

Consider the following calculation:

7 + 5 = 12

In the above example, 7, 5, and 12 are operands.

The operator+is used for addition.

The operator=is used for assignment.

TypeScript mainly includes the following types of operations:

• Arithmetic Operators
• Logical Operators
• Relational Operators
• Bitwise Operators
• Assignment Operators
• Ternary/Conditional Operators
• String Operators
• Type Operators

Arithmetic Operators

Assumey=5, the following table explains the operations of these arithmetic operators:

Example

Use thetsctsc command to compile the above code to get the following JavaScript code:

Executing the above JavaScript code produces the following output:

加:        12
减: 8
乘:    20
除:   5
余数:   0
num1 自增运算: 11
num2 自减运算: 1

Relational Operators

Relational operators are used to calculate whether the result is true or false.

x=5, the following table explains the operations of the relational operators:

Example

Use thetsctsc command to compile the above code to get the following JavaScript code:

Executing the above JavaScript code produces the following output:

num1 的值为: 5
num2 的值为:9
num1 大于n num2: false
num1 小于 num2: true
num1 大于或等于  num2: false
num1 小于或等于 num2: true
num1 等于 num2: false
num1 不等于 num2: true

Logical Operators

Logical operators are used to determine the logic between variables or values.

Given x=6 and y=3, the following table explains the logical operators:

Example

Use thetsctsc command to compile the above code to get the following JavaScript code:

Executing the above JavaScript code produces the following output:

avg 值为: 20 ,percentage 值为: 90
(avg>50)&&(percentage>80):  false
(avg>50)||(percentage>80):  true
!((avg>50)&&(percentage>80)):  true

Short-circuit Operators (&& and ||)

The && and || operators can be used to combine expressions. The && operator returns true only when both the left and right expressions are true.

Consider the following example:

var a = 10 
var result = ( a<10 && a>5)

In the above example, a < 10 and a > 5 are a combined expression using the && operator. The first expression returns false. Since the && operation requires both expressions to be true, if the first one is false, the subsequent evaluation (a > 5 is skipped) is not executed, and false is returned directly.

The || operator returns true for the combined expression as long as one of the expressions is true.

Consider the following example:

var a = 10 
var result = ( a>5 || a<10)

In the above example, a > 5 and a < 10 are a combined expression using the || operator. The first expression returns true. Since the || combined operation only requires one expression to be true, if the first one is true, the subsequent evaluation (a < 10 is skipped) is not executed, and true is returned directly.

Bitwise Operators

Bitwise operations are unary and binary operations on bit patterns or binary numbers in programming.

Example

Use thetsctsc command to compile the above code to get the following JavaScript code:

Executing the above JavaScript code produces the following output:

(a & b) =>  2
(a | b) =>  3
(a ^ b) =>  1
(~b) =>  -4
(a << b) =>  16
(a >> b) =>  0
(a >>> 1) =>  1

Assignment Operators

Assignment operators are used to assign values to variables.

Given x=10x=10 and y=5, the following table explains the assignment operators:

Similarly, logical operators can also be used in combination with assignment operators:<<=, >>=, >>>=, &=, |=and^=。

Example

Use thetsctsc command to compile the above code to get the following JavaScript code:

Execute the above JavaScript code, the output result is:

a = b: 10
a+=b: 20
a-=b: 10
a*=b: 100
a/=b: 10
a%=b: 0

Ternary Operator (?)

The ternary operation has 3 operands and needs to evaluate the value of a boolean expression. The main purpose of this operator is to decide which value should be assigned to a variable.

Test ? expr1 : expr2

• Test − The specified conditional statement
• expr1 − The value returned if the conditional statement Test evaluates to true
• expr2 − The value returned if the conditional statement Test evaluates to false

Let's look at the following example:

The example is used to determine whether the variable is greater than 0.

Use the tsc command to compile the above code and get the following JavaScript code:

The output of the above example is as follows:

小于 0，或等于 0

Type Operators

typeof Operator

typeof is a unary operator that returns the data type of the operand.

See the following example:

Use the tsc command to compile the above code and get the following JavaScript code:

The output of the above example is as follows:

number

instanceof

The instanceof operator is used to determine whether an object is of a specified type. We will introduce it in detail in later chapters.

Other Operators

Unary Negation Operator (-)

Changes the sign of the operand. See the following example:

Use the tsc command to compile the above code and get the following JavaScript code:

The output of the above example is as follows:

x 值为:  4
y 值为:  -4

String Operators: Concatenation Operator (+)

The + operator can concatenate two strings. See the following example:

Use the tsc command to compile the above code and get the following JavaScript code:

The output of the above example is as follows:

example.com