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javascriptdatetimedate-fns

How to create a JS Date object from weekday and time string

Given a string like Tue:18-20 how can one create a Javascript date object that represents the first/next Tuesday at 18:00 (from now)

For context: Above string format is used to store a users' pick-up and delivery times preferences. Keen to hear if there'd be a better approach to store this (either as a string or different format)

Solution

  • First, write a code to decode your <day>:<startHours>-<endHours> string. Then, You can do it like this

    let day = 1; // Mon : 1, Tue: 2, Wed: 3 ...
let startHours = 18;
let endHours= 20;

// get the start of the period
let dateStart = new Date();
dateStart.setDate(dateStart.getDate() + (day !== dateStart.getDay() ? (day + 7 - dateStart.getDay()) % 7 : 7));
dateStart.setHours(startHours, 0, 0, 0)
console.log(dateStart)

// get the end of the period
let dateEnd = new Date();
dateEnd.setDate(dateEnd.getDate() + (day !== dateEnd.getDay() ? (day + 7 - dateEnd.getDay()) % 7 : 7));
dateEnd.setHours(endHours, 0, 0, 0)
console.log(dateEnd)