Question

好的，我正在开发一个项目，用于使用StreamReader转换测量值来读取包含以下转换列表的文件：

ounce,gram,28.0
pound,ounce,16.0
pound,Kilogram,0.454
pint,litre,0.568
inch, centimetre,2.5
mile,inch,63360.0

当程序运行时，它会要求用户输入他们想要转换的金额，然后输入想要转换的测量值，然后输入他们想要转换成的测量值。所以例如5，盎司，克

获得输入后，程序会查看文件并计算转换率，因此5盎司= 140克，因此程序将显示为最终结果

＆＃34; 5盎司等于140克＆＃34;

我在这个程序中遇到的问题是StreamReader只读取convert.txt文件的第一行，例如，如果我要放2，磅，盎司它会返回第一行的文字后跟一条消息＆＃34; Not Matched＆＃34;所以它看起来像这样：

请输入类型的数量（Ex.5，盎司，克）： 2，磅，盎司盎司，克，28.0 不匹配

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
namespace Soft140AssPt3V2
{
class Program
{
    static void Main(string[] args)
    {
        string line, programStart, programEnd, j, l, lineTotal = "";//linetotal to take all lines from the file
        double factor, endResult, amount;
        string[] SplitData = new string[2];
        string[] fileLines;
        StreamReader unitsOfMeasurement = new StreamReader("../../convert.txt"); //Reads the convert.txt file
        Console.WriteLine("convert.txt has uploaded");
        while ((line = unitsOfMeasurement.ReadLine()) != null)
        {
            lineTotal += line + "\n";
        }
        fileLines = lineTotal.Split('\n');//place file lines in an array of string

        //Get inputs
        Console.WriteLine("\nPlease input the amount, to and from type (Ex. 5,ounces,grams):");
        string userInput = Console.ReadLine();
        for (int i = 0; i < fileLines.Length - 1; i++)
        {
            Console.WriteLine(fileLines[i]);
            SplitData = fileLines[i].Split(',');
            programStart = SplitData[0];
            programEnd = SplitData[1];
            factor = Convert.ToDouble(SplitData[2]);

            string[] filter = userInput.Split(',', ' ', '/', '.');
            amount = Convert.ToDouble(filter[0]);
            j = filter[1];
            l = filter[2];
            if (j == programStart)
            {
                endResult = (factor * amount);
                Console.WriteLine("\n{0} {1} equals {2} {3}", amount, filter[1], endResult, filter[2]);
                Console.ReadLine();


            }
            else
            {
                Console.WriteLine("Not Matched");
                Console.ReadLine();
            }
        }
        unitsOfMeasurement.Close();
    }
}
}

Answer 1

解决方案1：

StringBuilder lineTotal = new StringBuilder();
while ((line = unitsOfMeasurement.ReadLine()) != null)
{
    lineTotal.Append(line + Environment.NewLine);
}

fileLines =  lineTotal.ToString().Split(new string[]{Environment.NewLine},
                                  StringSplitOptions.RemoveEmptyEntries);

解决方案2：

StringBuilder lineTotal = new StringBuilder();
foreach(var line in File.ReadLines("../../convert.txt"))
{
lineTotal.Append(line);
}
fileLines =  lineTotal.ToString().Split(new string[]{Environment.NewLine},
                                  StringSplitOptions.RemoveEmptyEntries);

解决方案3：

string fileName = "../../convert.txt";
var lines = File.ReadLines(fileName).Where(line => 
                                !string.IsNullOrWhiteSpace(line)).ToArray();

Answer 2

以下是优化代码（您可以根据需要进一步修改代码）：

static void Main（string [] args） { 尝试 { 双重因素，endResult，金额; string [] fileLines;

            StreamReader unitsOfMeasurement = new StreamReader("../../convert.txt"); //Reads the convert.txt file
            Console.WriteLine("convert.txt has uploaded");

            fileLines = unitsOfMeasurement.ReadToEnd().Replace("\r\n", "\n").Split('\n');//place file lines in an array of string

            //Get inputs
            Console.WriteLine("\nPlease input the amount, to and from type (Ex. 5,ounce,gram):");
            string userInput = Console.ReadLine();

            bool blnFound = false;

            for (int i = 0; i < fileLines.Length; i++)
            {
                string[] filter = userInput.Split(',');

                if ((filter.Length == 3) && (filter[1].Trim() == fileLines[i].Split(',')[0].Trim()))
                {
                    blnFound = true;
                    Console.WriteLine(fileLines[i]);
                    factor = Convert.ToDouble(fileLines[i].Split(',')[2]);
                    amount = Convert.ToDouble(filter[0]);
                    endResult = (factor * amount);
                    Console.WriteLine("\n{0} {1} equals {2} {3}", amount, filter[1], endResult, filter[2]);
                    Console.ReadLine();
                    break;
                }
            }

            if (blnFound == false)
            {
                Console.WriteLine("Not Matched");
                Console.ReadLine();
            }

            unitsOfMeasurement.Close();
        }
        catch (Exception ex)
        {
            throw (ex);
        }
    }

使用StreamReader进行C＃测量转换仅从文件读取1行

2 个答案: