Kategóriák: Minden - conditional - functions - operators - math

a Brenda De la Cruz 5 éve

239

JavaScript

The text provides a comprehensive overview of JavaScript's capabilities in validating data and performing mathematical operations. It highlights the use of comparison and logical operators through conditional statements such as if, else, and else if.

JavaScript

Validación de datos

del cliente

del servidor

puede validar la entrada numérica

The else if Statement

if (condition1) { // block of code to be executed if condition1 is true } else if (condition2) { // block of code to be executed if the condition1 is false and condition2 is true } else { // block of code to be executed if the condition1 is false and condition2 is false }

The else Statement

if (condition) { // block of code to be executed if the condition is true } else { // block of code to be executed if the condition is false }

The if Statement

if (condition) { // block of code to be executed if the condition is true }

Comparing Different Types

age = Number(age); if (isNaN(age)) { voteable = "Input is not a number"; } else { voteable = (age < 18) ? "Too young" : "Old enough"; }

Conditional (Ternary) Operator

variablename = (condition) ? value1:value2

How Can it be Used

if (age < 18) text = "Too young";

Comparison Operators

true

Subtema

.abs()

Math.abs(-4.7); // returns 4.7

.sqrt ()

Math.sqrt(64); // returns 8

.pow()

Math.pow(8, 2); // returns 64

.round(x)

Math.round(4.7); // returns 5

JavaScript

Validation

if else and else if

Comparison and Logical Operators

Math Object