String and Number Conversion in JavaScript

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var myString = "999";

// Convert String to a number
var myNumber = +myString; // → 999
// OR
var myNumber = Number(myString) // → 999

// Convert String to negative number
var myNegativeNumber = -myString; // → -999
// OR
var myNegativeNumber = -Number(myString) // → -999

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