我需要从字符串前面剥去“标签”，例如
注意：这是一个注释
需要返回：
请注意
和
这是一张便条
我已经生成了以下代码示例，但是正在使用正则表达式。
我需要哪些代码？????????以下区域，以便我在评论中显示所需的结果？
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
namespace TestRegex8822
{
class Program
{
static void Main(string[] args)
{
List<string> lines = new List<string>();
lines.Add("note: this is a note");
lines.Add("test: just a test");
lines.Add("test:\t\t\tjust a test");
lines.Add("firstName: Jim"); //"firstName" IS a label because it does NOT contain a space
lines.Add("She said this to him: follow me."); //this is NOT a label since there is a space before the colon
lines.Add("description: this is the first description");
lines.Add("description:this is the second description"); //no space after colon
lines.Add("this is a line with no label");
foreach (var line in lines)
{
Console.WriteLine(StringHelpers.GetLabelFromLine(line));
Console.WriteLine(StringHelpers.StripLabelFromLine(line));
Console.WriteLine("--");
//note
//this is a note
//--
//test
//just a test
//--
//test
//just a test
//--
//firstName
//Jim
//--
//
//She said this to him: follow me.
//--
//description
//this is the first description
//--
//description
//this is the first description
//--
//
//this is a line with no label
//--
}
Console.ReadLine();
}
}
public static class StringHelpers
{
public static string GetLabelFromLine(this string line)
{
string label = line.GetMatch(@"^?:(\s)"); //???????????????
if (!label.IsNullOrEmpty())
return label;
else
return "";
}
public static string StripLabelFromLine(this string line)
{
return ...//???????????????
}
public static bool IsNullOrEmpty(this string line)
{
return String.IsNullOrEmpty(line);
}
}
public static class RegexHelpers
{
public static string GetMatch(this string text, string regex)
{
Match match = Regex.Match(text, regex);
if (match.Success)
{
string theMatch = match.Groups[0].Value;
return theMatch;
}
else
{
return null;
}
}
}
}
@Keltex，我将您的想法合并如下，但它不匹配任何文本（所有条目都是空白的），我需要在正则表达式中调整什么？
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
namespace TestRegex8822
{
class Program
{
static void Main(string[] args)
{
List<string> lines = new List<string>();
lines.Add("note: this is a note");
lines.Add("test: just a test");
lines.Add("test:\t\t\tjust a test");
lines.Add("firstName: Jim"); //"firstName" IS a label because it does NOT contain a space
lines.Add("first name: Jim"); //"first name" is not a label because it contains a space
lines.Add("description: this is the first description");
lines.Add("description:this is the second description"); //no space after colon
lines.Add("this is a line with no label");
foreach (var line in lines)
{
LabelLinePair llp = line.GetLabelLinePair();
Console.WriteLine(llp.Label);
Console.WriteLine(llp.Line);
Console.WriteLine("--");
}
Console.ReadLine();
}
}
public static class StringHelpers
{
public static LabelLinePair GetLabelLinePair(this string line)
{
Regex regex = new Regex(@"(?<label>.+):\s*(?<text>.+)");
Match match = regex.Match(line);
LabelLinePair labelLinePair = new LabelLinePair();
labelLinePair.Label = match.Groups["label"].ToString();
labelLinePair.Line = match.Groups["line"].ToString();
return labelLinePair;
}
}
public class LabelLinePair
{
public string Label { get; set; }
public string Line { get; set; }
}
}
好的，我得到了它的工作，加上一点点黑客来处理带有空格的标签，这正是我想要的，谢谢！
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
namespace TestRegex8822
{
class Program
{
static void Main(string[] args)
{
List<string> lines = new List<string>();
lines.Add("note: this is a note");
lines.Add("test: just a test");
lines.Add("test:\t\t\tjust a test");
lines.Add("firstName: Jim"); //"firstName" IS a label because it does NOT contain a space
lines.Add("first name: Jim"); //"first name" is not a label because it contains a space
lines.Add("description: this is the first description");
lines.Add("description:this is the second description"); //no space after colon
lines.Add("this is a line with no label");
lines.Add("she said to him: follow me");
foreach (var line in lines)
{
LabelLinePair llp = line.GetLabelLinePair();
Console.WriteLine(llp.Label);
Console.WriteLine(llp.Line);
Console.WriteLine("--");
}
Console.ReadLine();
}
}
public static class StringHelpers
{
public static LabelLinePair GetLabelLinePair(this string line)
{
Regex regex = new Regex(@"(?<label>.+):\s*(?<text>.+)");
Match match = regex.Match(line);
LabelLinePair llp = new LabelLinePair();
llp.Label = match.Groups["label"].ToString();
llp.Line = match.Groups["text"].ToString();
if (llp.Label.IsNullOrEmpty() || llp.Label.Contains(" "))
{
llp.Label = "";
llp.Line = line;
}
return llp;
}
public static bool IsNullOrEmpty(this string line)
{
return String.IsNullOrEmpty(line);
}
}
public class LabelLinePair
{
public string Label { get; set; }
public string Line { get; set; }
}
}
答案 0 :(得分：5)
难道你不能简单地将字符串拆分在第一个冒号上，或者如果没有冒号就没有标签吗？
public static class StringHelpers
{
public static string GetLabelFromLine(this string line)
{
int separatorIndex = line.IndexOf(':');
if (separatorIndex > 0)
{
string possibleLabel = line.Substring(0, separatorIndex).Trim();
if(possibleLabel.IndexOf(' ') < 0)
{
return possibleLabel;
}
}
else
{
return string.Empty;
}
}
public static string StripLabelFromLine(this string line)
{
int separatorIndex = line.IndexOf(':');
if (separatorIndex > 0)
{
return line.Substring(separatorIndex + 1,
line.Length - separatorIndex - 1).Trim();
}
else
{
return line;
}
}
public static bool IsNullOrEmpty(this string line)
{
return String.IsNullOrEmpty(line);
}
}
答案 1 :(得分：3)
它可能看起来像这样：
Regex myreg = new Regex(@"(?<label>.+):\s*(?<text>.+)");
Match mymatch = myreg.Match(text);
if(mymatch.IsMatch)
{
Console.WriteLine("label: "+mymatch.Groups["label"]);
Console.WriteLine("text: "+mymatch.Groups["text"]);
}
我上面使用了命名匹配，但你可以不使用它们。另外，我认为这比进行两次方法调用更有效。一个正则表达式同时获得文本和标签。
答案 2 :(得分：1)
此正则表达式有效（see it in action on rubular）：
(?: *([^:\s]+) *: *)?(.+)
这会将标签（如果有）捕获到\1，将正文捕获到\2。
它有足够的空格容差，因此标签可以缩进等等。