Typecast types in Typescript. That’s three “types” in a sentence with three significant words, and for that, I tap out.
Typecasting exists where type don’t exist. In Typescript types are not “cast” into other types. Typescript supports a way for you the developer to override default type inference for neutral types like
And, we have discussed about type assertion before.
Type assertion is simple enough -
const clueless:unknown = "1"; const clueNum:number= <number>clueless; // preferred format const clueNumPreferred = clueless as number;
See the aforementioned article to know more.
But, what if you want to actually cast a variable declared as one type to another in Typescript?
Then, my friend, you want type conversions. That is fairly familiar territory by now -
const position: string = "3"; const posNum: number = Number(position); console.log("posNum: ", posNum.toFixed(0)); // 3
.toFixed() is just to demonstrate that
3, the number, is indeed converted to
'3', the string.
The same is applicable for any other types.
const answer = 42; // auto inferred const life = String(answer); console.log("life: ", life.toLowerCase()); // 42