JavaScript Conditional Statements
We use conditional statements to perform different actions for different decisions. In JavaScript, we have the following conditional statements.
- Use if to specify a block of code to be executed, if a specified condition is true
- Use else to specify a block of code to be executed if the same condition is false
- Use else if to specify a new condition to test, if the first condition is false
- Use a switch to specify many alternative blocks of code to be executed
The if Statement
You can use the if statement to specify a block of JavaScript code to be executed if a condition is true.
Syntax
if (condition) {
a block of code to be executed if the condition is true
}
Example
If the marks of the student are more than 33 result will be passed.
if (marks > 33) {
result = “pass”;
}
The result will be:
Pass
The else Statement
Use the else statement to specify a block of code to be executed if the condition is false.
Syntax
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
}
Example
If the marks of the student are more than 33 result will be pass or less than 33 fail.
if (marks > 33) {
result = “pass”;
}
else {
result = “fail”;
}
The result will be:
Fail
The else if Statement
Use the else if statement to specify a new condition if the first condition is false.
Syntax
if (condition1) {
block of code to be executed if condition1 is true
} else if (condition2) {
block of code to be executed if condition1 is false and condition2 is true
} else {
block of code to be executed if condition1 is false and condition2 is false
}
Example:
