如果兩個東西不匹配，寫入文件末尾

Question

 counter = 0; 
     string line; 
     bool validCheck = true; 


     // Read the file and display it line by line. 
     System.IO.StreamReader file = 
      new System.IO.StreamReader(deckFile); 
     while ((line = file.ReadLine()) != null && validCheck == true) 
     { 
      if (line.Split(',')[1] == Form1.tempUsernameOut) 
      { 
       validCheck = false; 
      } 
      else 
      { 
       if (file.EndOfStream) 
       { 
        int lineCountDecks = File.ReadAllLines(deckFile).Length + 1; // Makes the variable set to the amount of lines in the deck file + 1. 
        string deckWriting = lineCountDecks.ToString() + "," + Form1.tempUsernameOut + ",1,,,,,,,,,,,2,,,,,,,,,,,3,,,,,,,,,,,4,,,,,,,,,,,5,,,,,,,,,,,"; // Stores what will be written in the deck file in a variable. 
        // Writes the contents of the variable "deckWriting" in the deck file. 
        StreamWriter writeFile = File.AppendText(deckFile); 
        writeFile.WriteLine(deckWriting); 
        writeFile.Close(); 

        validCheck = false; 
       } 
      } 
      counter++; 
     } 

     file.Close(); 

這是我到目前爲止，但它不起作用。這是我想要做的。如果文本文件中第一行的第二部分與tempUsernameOut匹配，則不執行任何操作。如果不匹配，請檢查下一行。檢查完所有行後，如果任何行的第二部分與tempUsernameOut不匹配，請將存儲在deckWriting中的行寫入文本文件的末尾。 我從這裏得到了代碼的基礎。謝謝！

https://msdn.microsoft.com/en-GB/library/aa287535(v=vs.71).aspx

Answer 1

起初，總是用 「使用」 採用流。這樣，即使發生異常，您也一定會關閉流。

你的問題在於你試圖寫入文件，當它被閱讀流阻止。 檢查是否需要，當你關閉讀數據流，這樣的事情

var counter = 0; 
string line; 
bool validCheck = true; 


     // Read the file and display it line by line. 
     using (var file = new System.IO.StreamReader(deckFile)) 
     { 
      while ((line = file.ReadLine()) != null && validCheck == true) 
      { 
       if (line.Split(',')[1] == Form1.tempUsernameOut) 
       { 
        validCheck = false; 
        break; 
       } 
       counter++; 
      } 
     } 

     if (validCheck) 
     { 
      int lineCountDecks = File.ReadAllLines(deckFile).Length + 1; 
      // Makes the variable set to the amount of lines in the deck file + 1. 
      string deckWriting = lineCountDecks.ToString() + "," + Form1.tempUsernameOut + 
           ",1,,,,,,,,,,,2,,,,,,,,,,,3,,,,,,,,,,,4,,,,,,,,,,,5,,,,,,,,,,,"; 
      // Stores what will be written in the deck file in a variable. 
      // Writes the contents of the variable "deckWriting" in the deck file. 
      using (var writeFile = File.AppendText(deckFile)) 
      { 
       writeFile.WriteLine(deckWriting); 
      } 
     } 

Answer 2

寫入文件或沒有，開流寫入使用的FileStream也許嘗試使用布爾變量。事情是這樣的：

using(FileStream fs = new FileStream(@"\\path\\to\\file", FileAccess.Write) 
using StreamWriter sw = new StreamWriter(fs) 
{ 
    sw.WriteLine(deckWriting); 
} 

Answer 3

這是更合適的方式來做到這一點：

counter = 0; 
    string line; 
    bool validCheck = true; 


    // Read the file and display it line by line. 
    using(StreamReader reader = File.OpenText(deckFile)) 
    { 
     while(!reader.EndOfStream && validCheck == true) 
     { 
      string line = reader.ReadLine(); 
      if (line.Split(',')[1] == Form1.tempUsernameOut) 
      { 
       validCheck = false; 
      } 

      counter++; //Already holds number of lines 
     } 
    } 

    if(validCheck) 
    { 
     using(StreamWriter writer = File.AppendText(deckFile)) 
     { 
      string deckWriting = string.Format("{0},{1},1,,,,,,,,,,,2,,,,,,,,,,,3,,,,,,,,,,,4,,,,,,,,,,,5,,,,,,,,,,,", counter, Form1.tempUsernameOut); 
      writer.WriteLine(deckWriting); 
     } 
    } 

一些評論：

1. 使用使用近，所以你的文件 「處理」 會在完成使用後關閉。

2. 只有當validCheck仍然爲true時才追加行。

3. 計數器已經佔用了行數。

4. 的String.format看起來更漂亮