Math.round无法正常工作 [英] Math.round not working

问题描述

我正在尝试使用Math.round的总数仅显示2个小数，但它不这样做.我在做什么错了?

I'm trying to use Math.round for the total to only show 2 decimals but it doesn't do that. What am I doing wrong?

$(document).ready(function() {
    var totalPrice = 0;

    $('.food').click(function() {
        var $frm = $(this).parent();
        var toAdd = $frm.children(".productInput").val();
        var addPrice = parseFloat($frm.children(".priceInput").val());
        var addAmount = parseFloat($frm.children(".amountInput").val());

        if ($('.priceInput').val() == '') {
            alert('Price can not be left blank');
        };
        if ($('.amountInput').val() == '') {
            alert('Amount can not be left blank');
        } else {

            var div = $("<div>");
            div.append("<p class='amount'>" + addAmount + "</p>", "<p class='product'> " + toAdd + " </p>", "<p class='price'>" + addPrice + "</p>", "<p class='delete'>" + "X" + "</p>");

            $frm.parent().children(".messages").append(div);

            totalPrice += addAmount * addPrice;

            $(".totalPrice").text("Total Price: $" + totalPrice);
        }


        console.log(addAmount);
        console.log(addPrice);
    });


    $(document).on("click", ".delete", function() {
        /*         var subAmount = parseFloat($(this).siblings(".amount").text());
                    var subPrice = parseFloat($(this).siblings(".price").text());
                    totalPrice -= subAmount * subPrice;
                    $(".totalPrice").text("Total Price: $" + totalPrice);*/

        $(this).closest("div").remove();
        console.log(subPrice);
        console.log(subAmount);
    });

    $(document).on("mouseover", ".delete", function() {
        var hoverAmount = parseFloat($(this).siblings(".amount").text());
        var hoverPrice = parseFloat($(this).siblings(".price").text());
        totalPrice -= hoverAmount * hoverPrice;
        Math.round(totalPrice * 100) / 100
        $(".totalPrice").text("Total Price: $" + totalPrice);

        $(this).closest("div").fadeTo("fast", 0.4);
    });
    $(document).on("mouseout", ".delete", function() {
        var subAmount = parseFloat($(this).siblings(".amount").text());
        var subPrice = parseFloat($(this).siblings(".price").text());
        totalPrice += subAmount * subPrice;
        Math.round(totalPrice * 100) / 100
        $(".totalPrice").text("Total Price: $" + totalPrice);


        $(this).closest("div").fadeTo("fast", 1.0);
    })





    });

由于我使用的是float格式，所以有时数字会变成小数点后的数字，而不是确切的数字.我试图通过使用Math.round来防止这种情况.如果有人对这个问题有其他解决方案，那也将不胜感激.

Since I'm using float, the numbers sometimes get changed into long decimals instead of the exact amount. I'm trying to prevent this by using Math.round. If anyone have another solution to the problem that would be appreciated too.

推荐答案

您Math.round不用了赋值变量，例如:

You Math.round is let alone without assignment variable such as:

totalPrice = Math.round(totalPrice * 100) / 100;
//  ^^ you're missing an assignment to store your operation result

这是另外两个小数的建议:

Here's another suggestion for the two decimals:

totalPrice = Number( (totalPrice * 100) / 100).toFixed(2) );
$(".totalPrice").text("Total Price: $" + totalPrice);

这篇关于Math.round无法正常工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！