Question: How to determine a cell is of Date type? about xlsx-populate

[Linus789]

This seems to work for me:

function isDate(cell): boolean {
    // https://foss.heptapod.net/openpyxl/openpyxl/-/blob/branch/3.1/openpyxl/styles/numbers.py
    let style = cell.style("numberFormat")

    if (typeof style !== 'string') {
        return false
    }

    const LITERAL_GROUP = /".*?"/g // anything in quotes
    const LOCALE_GROUP = /\[(?!hh?\]|mm?\]|ss?\])[^\]]*\]/g // anything in square brackets, except hours or minutes or seconds

    style = style.split(";")[0]
    style = style.replace(LITERAL_GROUP, "")
    style = style.replace(LOCALE_GROUP, "")
    return /(?<!\\)[dmhysDMHYS]/.test(style)
}