在 C# 中转换距离背后的逻辑错误

Question

应用程序：当用户输入数据时，我正在尝试将一种距离转换为另一种距离。但是，我的英寸到码和英寸到英尺的输出给我的逻辑错误为 0，而不是期望计算。英尺到码没有给我任何输出，码到码也在做同样的事情。我一直试图弄清楚 2 个小时，似乎无法理解。语法正确，逻辑与其他欲望输出相同。

我的代码：

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 Distance_Converter
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void ConvertButton_click(object sender, EventArgs e)
        {
            int distance_to_convert;
            string lengthOption1;
            string lengthOption2;
            int feet = 12; 




            lengthOption1 = FromListBox.SelectedItem.ToString();

            distance_to_convert = int.Parse(distancetoconvertTextBox.Text);

            if ((FromListBox.SelectedIndex) != 1 && (ToListBox.SelectedIndex) != -1)

                lengthOption1 = FromListBox.SelectedItem.ToString();
                lengthOption2 = ToListBox.SelectedItem.ToString();
            {
                switch (lengthOption1)
                {
                    case "Inches":
                        if (lengthOption2 == "Inches")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            int inches_feet = distance_to_convert / feet;
                            //int feet = 12; 
                            ConvertedDistanceTextBox.Text = inches_feet.ToString();
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            int inches_yard = distance_to_convert / 36;
                            ConvertedDistanceTextBox.Text = inches_yard.ToString();
                        }
                        break;
                    case "Feet":
                        if (lengthOption2 == "Inches")
                        {
                            int feet_inches = distance_to_convert * 12;
                            ConvertedDistanceTextBox.Text = feet_inches.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString(); ;
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            float  feet_yard = distance_to_convert / 3;
                            ConvertedDistanceTextBox.Text = feet_yard.ToString();
                        }
                        break;

                    case "Yards":
                        if (lengthOption2 == "Inches")
                        {
                            int Yards_inches = distance_to_convert * 36;
                            ConvertedDistanceTextBox.Text = Yards_inches.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            int Yards_feet = distance_to_convert * 3;
                            ConvertedDistanceTextBox.Text = Yards_feet.ToString();
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString(); ;
                        }
                        break;
                }
            }

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

Answer 1

将 int 作为存储结果的变量的数据类型会导致问题。如果将除法的结果存储在整数变量中，它只存储整数。

考虑将inches_yard 和其他变量的数据类型更改为float、decimal 或double。

                    else if (lengthOption2 == "Yards")
                    {
                        double inches_yard = distance_to_convert / 36;  //changed datatype from int to double here
                        x = inches_yard.ToString();
                    }

Answer 2

如 cmets 中所述。当您存储为 int 时，分数将为零。 使用此代码 sn-p。您将在结果中得到非零值

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 Distance_Converter
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void ConvertButton_click(object sender, EventArgs e)
        {
            int distance_to_convert;
            string lengthOption1;
            string lengthOption2;
            int feet = 12; 
            lengthOption1 = FromListBox.SelectedItem.ToString();    
            distance_to_convert = int.Parse(distancetoconvertTextBox.Text);

            if ((FromListBox.SelectedIndex) != 1 && (ToListBox.SelectedIndex) != -1)

                lengthOption1 = FromListBox.SelectedItem.ToString();
                lengthOption2 = ToListBox.SelectedItem.ToString();
            {
                switch (lengthOption1)
                {
                    case "Inches":
                        if (lengthOption2 == "Inches")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            double inches_feet = (double)distance_to_convert / feet;
                            //int feet = 12; 
                            ConvertedDistanceTextBox.Text = inches_feet.ToString();
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            double inches_yard = (double)distance_to_convert / 36;
                            ConvertedDistanceTextBox.Text = inches_yard.ToString();
                        }
                        break;
                    case "Feet":
                        if (lengthOption2 == "Inches")
                        {
                            double feet_inches = (double)distance_to_convert * 12;
                            ConvertedDistanceTextBox.Text = feet_inches.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString(); ;
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            float  feet_yard =(float) distance_to_convert / 3;
                            ConvertedDistanceTextBox.Text = feet_yard.ToString();
                        }
                        break;

                    case "Yards":
                        if (lengthOption2 == "Inches")
                        {
                            double Yards_inches = (double)distance_to_convert * 36;
                            ConvertedDistanceTextBox.Text = Yards_inches.ToString();
                        }
                        else if (lengthOption2 == "Feet")
                        {
                            double Yards_feet = (double) distance_to_convert * 3;
                            ConvertedDistanceTextBox.Text = Yards_feet.ToString();
                        }
                        else if (lengthOption2 == "Yards")
                        {
                            ConvertedDistanceTextBox.Text = distance_to_convert.ToString(); ;
                        }
                        break;
                }
            }

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