Question

如何从特定位置读取文本文件，例如我有文本文件

pathA = sometexthere$
pathB = sometexthere$
pathC = sometexthere$
TimerTC = sometexthere$

我想阅读＆＃34; =＆＃34;之间的所有内容。和＆＃34; $＆＃34;

使用以下方法逐行阅读：

int counter = 0;
string line;

System.IO.StreamReader file = new System.IO.StreamReader("config.cfg");

while((line = file.ReadLine()) != null)
{
    if (counter == 1)
    {
        label1.Text=line;
        counter++;
    }
    else if (counter == 2)
    {
        label2.Text=line;
        counter++;
    }
}

Answer 1

您可以使用SkipWhile和TakeWhile方法：

File.ReadLines("path")
    .Select(line => new string(line
                   .SkipWhile(c => c != '=')
                   .Skip(1)
                   .TakeWhile(c => c != '$').ToArray())).ToList();

Answer 2

解决方案1：

int index;

List<string> listLines = new List<string>();
foreach (var line in File.ReadLines("C:\\Data.txt"))
{
   index = line.LastIndexOf('=');
   listLines.Add(line.Substring(index + 1, (line.Length - index) - 
                                     ((line.Length) - line.LastIndexOf('$')+1)));
}

<强>溶液2：

您可以使用分隔符=拆分每一行，然后提取以=开头的单词$

string str;
List<string> listLines = new List<string>();
foreach (var line in File.ReadLines("C:\\Data.txt"))
{
    str = line.Split('=')[1].Trim();
    listLines.Add(str.Substring(0, str.Length - 
                                           (str.Length - str.LastIndexOf('$'))));
}

解决方案3：

List<string> listLines = new List<string>();
foreach (var line in File.ReadLines("C:\\Data.txt"))
{
    var str = line.Split(new char[] { '=', '$'},
                                         StringSplitOptions.RemoveEmptyEntries);
    listLines.Add(str[1].Trim());
}

Answer 3

您也可以使用正则表达式（although, now you have two problems）执行此操作：

var regex = new Regex(
   @"^             # beginning of the line
    (?<key>.*?)    # part before the equals sign 
    \s*=\s*        # `=` with optional whitespace
    (?<value>.*)   # part after the equals sign 
    \$             # `$`
    $              # end of the line",
    RegexOptions.Multiline |
    RegexOptions.IgnorePatternWhitespace |
    RegexOptions.Compiled);

或者，一个班轮：

var regex = new Regex(@"^(?<key>.*?)\s*=\s*(?<value>.*)\$$");

然后选择匹配到键值对：

var keyValuePairs = File
    .ReadLines("config.cfg")
    .Select(line => regex.Match(line))
    .Where(match => match.Success)
    .Select(match => new
        {
            Key = match.Groups["key"].Value,
            Value = match.Groups["value"].Value
        })
    .ToList();

从文本文件中读取值，用=和$符号分隔

3 个答案: