When converting one type to another in TypeScript, you may encounter type errors if the conversion is not valid. TypeScript provides type annotations and type inference to help catch such errors during development. Here are some common scenarios and solutions for type conversion errors:

  1. Converting between primitive types: If you are trying to convert between primitive types such as numbers, strings, or booleans, you can use type casting using type assertion, as shown below:
typescript
const num: number = 42; const str: string = 'Hello'; const bool: boolean = true; // Converting number to string const numToStr: string = num.toString(); // Converting string to number const strToNum: number = parseInt(str); // Converting boolean to string const boolToStr: string = bool.toString(); // Converting string to boolean const strToBool: boolean = str === 'true';
  1. Converting between custom types: If you have custom types or interfaces defined in your TypeScript code and you need to convert between them, you can use type casting using type assertion or create conversion functions or methods, as shown below:
typescript
interface Person { name: string; age: number; } interface Employee { name: string; position: string; } const person: Person = { name: 'John', age: 30 }; // Converting Person to Employee using type assertion const employee: Employee = person as Employee; // Converting Person to Employee using a conversion function function convertPersonToEmployee(person: Person): Employee { return { name: person.name, position: 'Manager' }; } const employee2: Employee = convertPersonToEmployee(person);
  1. Converting between arrays and other types: If you need to convert between arrays and other types, such as tuples or objects, you can use TypeScript's built-in array methods or type casting, as shown below:
typescript
const arr: number[] = [1, 2, 3, 4, 5]; // Converting array to tuple const tuple: [number, number, number, number, number] = arr as [number, number, number, number, number]; // Converting array to object const obj: Record<string, number> = arr.reduce((acc, num, index) => { acc[`key${index}`] = num; return acc; }, {} as Record<string, number>);

Note: While type casting using type assertion can be useful for type conversion, it should be used with caution as it bypasses TypeScript's type checking. It's important to ensure that the conversion is valid and the resulting type is used correctly in your code to avoid runtime errors. It's generally safer to use conversion functions or methods that explicitly define the expected input and output types.

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