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Get type of a variable in string

Written byPhuoc Nguyen
12 Jan, 2021
Last updated
13 Oct, 2021
JavaScript version
const getTypeOf = (obj) => Object.prototype.toString.call(obj).match(/\[object (.*)\]/)[1];
TypeScript version
const getTypeOf = (obj: any): string => (Object.prototype.toString.call(obj).match(/\[object (.*)\]/) as string[])[1];
getTypeOf('hello world'); // String
getTypeOf(1000); // Number
getTypeOf(Infinity); // Number
getTypeOf(true); // Boolean
getTypeOf(Symbol()); // Symbol
getTypeOf(null); // Null
getTypeOf(undefined); // Undefined
getTypeOf({}); // Object
getTypeOf([]); // Array
getTypeOf(/[a-z]/g); // RegExp
getTypeOf(new Date(2021)); // Date
getTypeOf(new Error()); // Error
getTypeOf(function () {}); // Function
getTypeOf((a, b) => a + b); // Function
getTypeOf(async () => {}); // AsyncFunction
getTypeOf(document); // HTMLDocument

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