c# - 尝试删除字符串的最后一个字符时出错

Question

我正在尝试删除字符串的最后一个 "," 但是我收到一条错误消息

System.ArgumentOutOfRangeException: 'StartIndex cannot be less than zero.

字符串写入文件正常，但在运行时出现上述错误时中断。我不确定为什么会这样，如有任何建议，我们将不胜感激。

我使用的代码如下

for (int z = 0; z <= totalNumberOfCaves; z++)
    {
        for (int i = 0; i < totalNumberOfCaves && connectionStack.Count > 0; i++)
        {
            connectionData.Add(int.Parse(connectionStack.Pop()));
        }
        string fileName2 = @"D:\UNI\Year 5\AI - SET09122\SET09122 - CW1\WriteConnectionData.txt";
        string writeUnEditedData = "";        
        foreach (int s in connectionData)
        {
            writeUnEditedData += (s + ",");
        }
    using (StreamWriter sw = File.AppendText(fileName2))
    {
        string writeData = writeUnEditedData.Remove(writeUnEditedData.Length - 1);
        sw.Write("{ " + writeData + " }," + Environment.NewLine);            
    }
    connectionData.Clear();
}

Answer 1

在循环中追加 string:

    foreach (int s in connectionData)
    {
        writeUnEditedData += (s + ",");
    }

不是一个好主意。将 加入:

    writeUnEditedData = string.Join(",", connectionData); 

完成此操作后，您无需删除任何内容:

 using (StreamWriter sw = File.AppendText(fileName2))
 { 
     // No Remove here
     string writeData = writeUnEditedData;
     ...