C# 我怎样才能使它不会使货币四舍五入呢？

我一直在尝试构建一个简单的小费计算器，并获得小费应该是多少的精确值。我已经完成了大部分，但我正在努力找到小数点后的两个精确数字，因为它一直在舍入它们。有人能帮忙吗

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace project01LEA
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void exitToolStripMenuItem1_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void aboutToolStripMenuItem_Click(object sender, EventArgs e)
        {
            MessageBox.Show("Lyndsee Armstrong\nCSIS 1400\nProject #1");
        }

        private void textBox1_Leave(object sender, EventArgs e)
        {
            //define variables
            const double POOR = 0.10;
            const double AVERAGE = 0.15;
            const double EXCELLENT = 0.20;

            double mealAmount = Convert.ToDouble(textBox1.Text);

            double doubledPoor = Convert.ToInt32(POOR * mealAmount);
            double doubledAverage = Convert.ToInt32(AVERAGE * mealAmount);
            double doubledExcellent = Convert.ToInt32(EXCELLENT * mealAmount);

            string outStr = string.Format("{0:C2}", doubledPoor);
            string outStr1 = string.Format("{0:C2}", doubledAverage);
            string outStr2 = string.Format("{0:C2}", doubledExcellent);

            textBox2.Text = outStr;
            textBox3.Text = outStr1;
            textBox4.Text = outStr2;
        }
    }
}

---

您的问题是

Convert.ToInt32

——它将浮点值更改为整数值，而整数不包含小数。如果您删除了这些行，这应该完全符合您的需要（字符串格式看起来很正确）。

在显示代码时，您应该标记语言（这有助于人们找到您的问题，也会影响语法突出显示）。我给你加上了c标签。