程序在输出完成写入文件之前结束

Question

As the title suggests, I have a program that ends before it has finished writing its output to a file. I'm not sure if this is a limitation of C# or what.

Here is the code in question:

    static void Main(string[] args)
    {
        StreamReader source = new StreamReader(filepathsource);
        StreamWriter dest = new StreamWriter(filepathdest,false);

        dest.WriteLine("Department,Number,Long Title,Description");

        string line;
        bool dept = false;
        bool num = false;
        bool title = false;
        string temp;

        while ((line = source.ReadLine()) != null)
        {
            dept = false;
            num = false;
            title = false;
            temp = "";

            line = line.TrimStart(' ', '\t');
            if (line.Length > 0)
            {
                foreach (char z in line)
                {
                    if (!dept)
                    {
                        if (z == ' ') //---a space will mark the end of the department code.
                        {
                            dept = true;
                            temp += ",\""; //make a comma and a double quote to ensure the number that follows is a string
                        }
                        else
                            temp += z;
                    }
                    else if (!num)
                    {
                        if (z == '.') //---a period will mark the end of the course number
                        {
                            num = true;
                            temp += "\",\""; //close the string, make a comma, and start a new string
                        }
                        else
                            temp += z;
                    }
                    else if (!title) 
                    {
                        if (z == '.') //---a period will mark the end of the course title
                        {
                            title = true;
                            temp += "\",\""; //close the string, make a comma, and start a new string
                        }
                        else
                            temp += z;
                    }
                    else if(z == '"') //---We are in the Description now and if we find a double quote
                    {
                        temp += "''";  //replace it with two single quotes
                    }
                    else
                        temp += z;
                }
                temp += "\""; //---end the last string
                dest.WriteLine(temp); //---write the comma delimited line to the output file.
            }
        }
    }

The program is designed to pull course catalog information from a text file (ASCII or Unicode agnostic), parse it as it follows a specific format, and then separate it out into fields that are injected into another text file as in CSV format. This CSV formatted info would then be merged into a MSSQL database.

It seems to me however that the longer the information in the source file, the more issues the program has with cutting out the last few lines of text. What can I do to correct this? I ran the program last year on old information and it seemed to run just fine.

Answer 1

Always close streams after you use them.

At the end add:

dest.Close();
source.Close();

A better approach is also to put them in a using statement:

static void Main(string[] args)
{
  using(StreamReader source = new StreamReader(filepathsource))
  {
     using(StreamWriter dest = new StreamWriter(filepathdest,false))
     {
       dest.WriteLine("Department,Number,Long Title,Description");

       string line;
       bool dept = false;
       bool num = false;
       bool title = false;
       string temp;

       while ((line = source.ReadLine()) != null)
       {
          ......
       }
    }
  }
}

Answer 2

Add the following outside of your while loop

dest.Flush();

or set Auto flush to true / close the stream. See here for more info.