数字转两位小数金额

function formatCount(count) {
    var string = String(count || 0)
    if (!string) {
        return ''
    }
    var index = string.indexOf('.')
    if (index != -1) {
        string += '00'
        var num = 0
        if (Number(string.substring(index + 3, index + 4) || 0) >= 5) {
            num = 1
        }
        string = string.substring(0, index + 3)
        if (num > 0) {
            return formatCount(Math.round(Number(string) * 100 + num) / 100)
        }
    } else {
        string += '.00'
    }
    return string
}

直接截掉后面的小数，转成'xx.xx'的形式