JS格式化钱金额加上逗号

 function formatPrice(val: string | number, precision: number = 2) {
    if (typeof val === 'string') {
        let num = parseFloat(val)
        if (isNaN(num) || num.toString() !== val) {
            return val;
        }
    }
    let [integer, decimal = ''] = String(val).split('.')
    decimal = decimal
        .padEnd(precision, '0')
        .slice(0, precision > 0 ? precision : 0)
    integer = integer.replace(/\B(?=(\d{3})+(?!\d))/g, ',')
    return [integer, decimal].join(decimal ? '.' : '')

}