JavaScript Operators
= is used to assign values.
+ is used to add values.
The assignment operator = is used to assign values to JavaScript variables.
The arithmetic operator + is used to add values together.
Example
Assign values to variables and add them together:
y=5;
z=2;
x=y+z;
z=2;
x=y+z;
The result of x will be:
7
JavaScript Arithmetic Operators
Arithmetic operators are used to perform arithmetic between variables and/or values.
Given that y=5, the table below explains the arithmetic operators:
Operator | Description | Example | Result of x | Result of y | |
---|---|---|---|---|---|
+ | Addition | x=y+2 | 7 | 5 | |
- | Subtraction | x=y-2 | 3 | 5 | |
* | Multiplication | x=y*2 | 10 | 5 | |
/ | Division | x=y/2 | 2.5 | 5 | |
% | Modulus (division remainder) | x=y%2 | 1 | 5 | |
++ | Increment | x=++y | 6 | 6 | |
x=y++ | 5 | 6 | |||
-- | Decrement | x=--y | 4 | 4 | |
x=y-- | 5 | 4 |
JavaScript Assignment Operators
Assignment operators are used to assign values to JavaScript variables.
Given that x=10 and y=5, the table below explains the assignment operators:
Operator | Example | Same As | Result | |
---|---|---|---|---|
= | x=y | x=5 | ||
+= | x+=y | x=x+y | x=15 | |
-= | x-=y | x=x-y | x=5 | |
*= | x*=y | x=x*y | x=50 | |
/= | x/=y | x=x/y | x=2 | |
%= | x%=y | x=x%y | x=0 |
The + Operator Used on Strings
The + operator can also be used to add string variables or text values together.
Example
To add two or more string variables together, use the + operator.
txt1="What a very";
txt2="nice day";
txt3=txt1+txt2;
txt2="nice day";
txt3=txt1+txt2;
The result of txt3 will be:
What a verynice day
To add a space between the two strings, insert a space into one of the strings:
Example
txt1="What a very ";
txt2="nice day";
txt3=txt1+txt2;
txt2="nice day";
txt3=txt1+txt2;
The result of txt3 will be:
What a very nice day
or insert a space into the expression:
Example
txt1="What a very";
txt2="nice day";
txt3=txt1+" "+txt2;
txt2="nice day";
txt3=txt1+" "+txt2;
The result of txt3 will be:
What a very nice day
Adding Strings and Numbers
Adding two numbers, will return the sum, but adding a number and a string will return a string:
Example
x=5+5;
y="5"+5;
z="Hello"+5;
y="5"+5;
z="Hello"+5;
The result of x,y, and z will be:
10
55
Hello5
55
Hello5
The rule is: If you add a number and a string, the result will be a string!