Reading-notes

Operators :

• Assignment operators :

  An assignment operator assigns a value to its left operand based on the value of its right operand : example ` x = y`;

• Comparison operators:

  A comparison operator compares its operands and returns a logical value based on whether the comparison is true. example var2 > var1

• Arithmetic operators:

  An arithmetic operator takes numerical values as their operands and returns a single numerical value .example : 1 / 2;

• Bitwise operators :

  A bitwise operator treats their operands as a set of 32 bits (zeros and ones). example: a & b

• Logical operators :

  Logical operators are typically used with Boolean (logical) values . example : expr1 && expr2

• String operators :

  example : var mystring = 'alpha';

• Comma operator :

  evaluates both of its operands and returns the value of the last operand .

• Unary operators:

  delete The delete operator deletes an object’s property. The syntax is: ` delete object.property;`

• Relational operators:

  in The in operator returns true if the specified property is in the specified object.

Loops and iteration:

Loops offer a quick and easy way to do something repeatedly. This chapter of the JavaScript Guide introduces the different iteration statements available to JavaScript.

1- for statement:

A for loop repeats until a specified condition evaluates to false. The JavaScript for loop is similar to the Java and C for loop.

for ([initialExpression]; [conditionExpression]; [incrementExpression]) statement

2- do…while statement:

The do…while statement repeats until a specified condition evaluates to false.

do

` statement`

while (condition);

3- while statement

A while statement executes its statements as long as a specified condition evaluates to true.

while (condition)

statement

## 4-break statement Use the break statement to terminate a loop, switch, or in conjunction with a labeled statement.

break;

break [label];

5- for…in statement

The for…in statement iterates a specified variable over all the enumerable properties of an object.

for (variable in object)

` statement`