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JavaScript Operators
Addition Assignment Operator (+=) (JavaScript)
Addition Operator (+) (JavaScript)
Assignment Operator (=) (JavaScript)
Bitwise AND Assignment Operator (&=) (JavaScript)
Bitwise AND Operator (&) (JavaScript)
Bitwise Left Shift Operator (<<) (JavaScript)
Bitwise NOT Operator (~) (JavaScript)
Bitwise OR Assignment Operator (|=) (JavaScript)
Bitwise OR Operator (|) (JavaScript)
Bitwise Right Shift Operator (>>) (JavaScript)
Bitwise XOR Assignment Operator (^=) (JavaScript)
Bitwise XOR Operator (^) (JavaScript)
Comma Operator (,) (JavaScript)
Comparison Operators (JavaScript)
Compound Assignment Operators (JavaScript)
Conditional (Ternary) Operator (?:) (JavaScript)
delete Operator (JavaScript)
Division Assignment Operator (/=) (JavaScript)
Division Operator (/) (JavaScript)
in Operator (JavaScript)
Increment (++) and Decrement (--) Operators (JavaScript)
instanceof Operator (JavaScript)
Left Shift Assignment Operator (<<=) (JavaScript)
Logical AND Operator (&&) (JavaScript)
Logical NOT Operator (!) (JavaScript)
Logical OR Operator (||) (JavaScript)
Modulus Assignment Operator (JavaScript)
Modulus Operator (JavaScript)
Multiplication Assignment Operator (*=) (JavaScript)
Multiplication Operator (*) (JavaScript)
new Operator (JavaScript)
Right Shift Assignment Operator (>>=) (JavaScript)
Subtraction Assignment Operator (-=) (JavaScript)
Subtraction Operator (-) (JavaScript)
typeof Operator (JavaScript)
Unsigned Right Shift Assignment Operator (>>>=) (JavaScript)
Unsigned Right Shift Operator (>>>) (JavaScript)
void Operator (JavaScript)
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Logical AND Operator (&&) (JavaScript)

JavaScript - Internet Explorer 10

Performs a logical conjunction on two expressions.

Copy 
result = expression1 && expression2
result

Any variable.

expression1

Any expression.

expression2

Any expression.

If both expressions evaluate to true, result is true. If either expression evaluates to false, result is false.

JavaScript uses the following rules for converting non-Boolean values to Boolean values:

  • All objects are considered to be true.

  • Strings are considered to be false if they are empty.

  • null and undefined are considered to be false.

  • A Number is false if it is zero.

Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards. Also supported in Windows Store apps. See Version Information.

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