JavaScript type conversions, operators, statements

1. Type conversion:

　　It is divided into automatic conversion and casting, which is generally used for casting.

Other types are converted to integers: parseint ();

Other types convert to decimals: parsefloat ();

Determine if it is a valid number type: IsNaN ();

is a number then returns false, not a number to return ture.

Example:

2. Operators:

　　Math operator : +-*/% + +-;

　　relational operators : = =! = >= <= > <;

　　logical operator :&& | | ！ ；

　　Other operators : + = = *=/=%=? ；

3. Statement:

　It is generally divided into sequential, branching, and cyclic statements.

(1) Branch statement if:

if (judging condition)

{

Statements that meet the criteria to be executed

}

Else

{

Statements executed when a condition is not met

}

(2) Loop for statement:

For ( initial condition; cyclic condition; state change )

{

　　Loop body

}

(3) Problem type: exhaustive, iterative.

(4) Two keywords: break and continue.

(5) If you want to output the value of a parameter: the value of the output is "+a+" and "+b"

JavaScript type conversions, operators, statements