JavaScript Conditional Statement--branch statement-4

Learning Goals

1. Mastering the Conditional statement if

2. Mastering The application of prompt ()

3. Mastering The application of alert

If Statement

Syntax One:

If (condition) {

Statement1

}

Prompt ()

Syntax:prompt ()

Function: Popup input Box

return Value: 1. Click OK to return to the input content

2. Click Cancel to return null

Alert ()

Syntax:alert ()

Features: Pop-up warning dialog box

If Statement

Syntax Two:

If (condition) {

Statement1;

}else{

Statement2;

}

If Statement

Syntax Three:

If (condition) {

Statement1;

}else if (condition) {

Statement2;

}else{

Statement2

}

JavaScript Conditional Statement--branch statement-4