In this typescript tutorial, we will see how to convert a string to boolean in typescript. Here are the examples we are going to cover:
- Using the
Boolean
constructor - Using a ternary operator to check if the string equals “true”
- Using the double exclamation mark
!!
operator - Using a switch statement
Using the Boolean
constructor
Here we will see how to convert a string to a boolean using the boolean constructor in typescript.
The boolean constructor in typescript is used to convert a string to a boolean. The constructor takes a value as an argument and returns a boolean value. When a non-empty string value is passed, the returned boolean value will be true.
Open the code editor, create a file named as ‘convertStringToBoolean ‘, and then write the below code:
const str = 'true';
const boolValue = Boolean(str); // boolValue is true
To compile the code, run the below command and you can see the result in the console:
ts-node convertStringToBoolean

This is an example of typescript for converting a string to a boolean using the boolean constructor.
Using a ternary operator to check if the string equals “true”.
Here we will see an example of how to convert a string to a boolean using a ternary operator to check the string equals “true” in typescript.
The ternary operator in typescript is a shorthand way of writing an if-else statement. It can also be used to convert a string to a boolean value by checking if the string is equal to “true” and returning true or false accordingly.
In the convertStringToBoolean.ts file, write the below code
const str = 'false';
const boolValue = str === 'false' ? true : false;
console.log(boolValue);// boolValue is true
To compile the code run the below command and you can see the result in the console
ts-node convertStringToBoolean

This is an example of converting a string to a boolean using a ternary operator to check the string equals true in typescript.
Using the double exclamation mark !! operator
Here we will see an example of converting a string to a boolean using the double exclamation !! operator.
For example, we will take a string as”false”, it is converted to a boolean value using the double exclamation mark !! operator, which returns a boolean value of false.
In the convertStringToBoolean.ts file, write the below code:
const str = "false";
const boolValue = !!str;
console.log(boolValue);
To compile the code and run the below command and you can see the result in the console:
ts-node convertStringToBoolean

This is how we can convert a string to boolean in typescript using double exclamation.
Using a switch statement
Here we will see an example of converting a string to a boolean value, using a switch statement in typescript.
A switch statement in typescript can be used to check different cases of a string and convert it to a boolean value based on the case.
In the convertStringToBoolean.ts file, write the below code:
const str:string = 'false';
let boolValue: boolean;
switch(str) {
case 'true':
boolValue = true;
break;
case 'false':
boolValue = false;
break;
default:
throw new Error('Invalid string value');
}
console.log(boolValue);
To compile the code and run the below command and you can see the result in the console:
ts-node convertStringToBoolean

This is an example of how we can convert a string to a boolean value using a switch statement in typescript.
Conclusion
In this typescript tutorial, we saw how we can convert a string to a boolean value in typescript. Also, we saw different ways to convert a string to a boolean value:
- Using the
Boolean
constructor - Using a ternary operator to check if the string equals “true”
- Using a switch statement
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- How to check if string contains only numbers in typescript
- Typescript convert string to keyof
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- Typescript string capitalize first letter
- How to create a multiline string in typescript
I am Bijay a Microsoft MVP (8 times –Â My MVP Profile) in SharePoint and have more than 15 years of expertise in SharePoint Online Office 365, SharePoint subscription edition, and SharePoint 2019/2016/2013. Currently working in my own venture TSInfo Technologies a SharePoint development, consulting, and training company. I also run the popular SharePoint website EnjoySharePoint.com