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JavaScript Conditionalif and if...elseThe if statement is one of the most common statements you will use. Here's the syntax:
if (condition){
[statement(s)]
}
The condition can be any logical expression. the [statements] between the brackets { } will execute if the statement test out to be true. If you want to execute a block of statements when the if statement is false, then you use the else statement.
if(condition){
[statement(s)]
}
else{
[statement(s)]
}
You can also put an if statement after else for the code to execute if the first statement is false and if this statement is true.
if(condition){
[statement(s)]
}
else if(condition){
[statement(s)]
}
else{
[statement(s)]
}
switchThe Switch statement if you want to select one of many blocks of code to be executed.
switch(expression)
{
case condition:
code to be executed if condition is true
break
case condition:
executed if this condition is true
break
... as many case expressions...
default:
code executed if all cases evaluated to be false
}
Each case will evaluate, if it is ture, the block of code will be executed, the break statement is to prevent further evaluation of the different variables. The default: statement at the end of the switch statement is required, if all cases evaluate to be false then the default block is activated. Conditional OperatorThere is also a way to assign a value to a variable based on a condition. The syntax is as follows...
variable = (condition)? value1 : value2
eg:
theDate = (today == "monday")? "true" : "false"
The first value, true will be stored to theDate if the expression (today == "monday") is true, while value2, false, will be stored to theDate if the expressions evaluates to be false |
