JSFiddle - React, Tailwind, and code Playground

JavaScript

function GetStartAndEnd(dateRange, bGetFullRange) {
    var dateObject = new Date();

    var dateobj = new Date()
    var month = dateobj.getMonth()+1
    var day = dateobj.getDate()
    var year = dateobj.getFullYear()


    var start = undefined;
    var end = undefined;
    if (dateRange.toLowerCase() == "today") {
        start = month + "/" + day + "/" + year;
        end = month + "/" + day + "/" + year;
    } else if (dateRange.toLowerCase() == "this week") {
        var curr = new Date;
        var firstDay = new Date(curr.setDate(curr.getDate() - curr.getDay()));
        var lastDay = new Date(curr.setDate(curr.getDate() - curr.getDay() + 6));

        var fmonth = firstDay.getMonth()+1;
        var fday = firstDay.getDate();
        var fyear = firstDay.getFullYear();
        start = fmonth + "/" + fday + "/" + fyear;

        var lmonth = lastDay.getMonth()+1;
        var lday = lastDay.getDate();
        var lyear = lastDay.getFullYear();
        end = lmonth + "/" + lday + "/" + lyear;

    } else if (dateRange.toLowerCase() == "this month" && bGetFullRange) {
        var date = new Date(),
            y = date.getFullYear(),
            m = date.getMonth();
        var firstDay = new Date(y, m, 1);
        var lastDay = new Date(y, m + 1, 0);


        var fmonth = firstDay.getMonth()+1;
        var fday = firstDay.getDate();
        var fyear = firstDay.getFullYear();
        start = fmonth + "/" + fday + "/" + fyear;

        var lmonth = lastDay.getMonth()+1;
        var lday = lastDay.getDate();
        var lyear = lastDay.getFullYear();
        end = lmonth + "/" + lday + "/" + lyear;

    } else if (dateRange.toLowerCase() == "this month" && !bGetFullRange) {
        var date = new Date(),
            day = date.getDate(),
            y = date.getFullYear(),
            m = date.getMonth();
        var firstDay = new Date(y, m, 1);
        var lastDay = new Date(y, m + 1, 0);


        var fmonth = firstDay.getMonth()+1;
        var fday =...