Question

好的，所以我的代码看起来有点像这样

        // Returns the note of a favorite pown if it exists
        string GetFavoriteNote(int id)
        {
            string notelist = Properties.Settings.Default.FavoriteNotesList;

            // If there's a note, return it
            if (notelist.Contains("'" + id + ":"))
            {
                // What to do here?
            }
            // If there's no note, return an empty string
            else
            {
                return String.Empty;
            }
        }

现在它基本上是一个系统，用户可以为每个ID设置一个注释，它将以这种格式保存：'id:note','id:note'，

现在我要做的是以某种方式选择该注释并将其返回，因此我必须选择从"'" + id + ":"中选择直到'

如果有人知道怎么做，请帮帮我。谢谢

Answer 1

使用正则表达式对我来说似乎是最干净的方法：

string regexFormat = "'{0}:(.*?)'";
Match match = Regex.Match(notelist, string.Format(regexFormat, id));
return match.Success ? match.Groups[1].Value : string.Empty;

但是，您也可以使用字符串拆分：

var notes = notelist.Split(',');
var idString = "'" + id + ":";
var note = notes.FirstOrDefault(n => n.StartsWith(idString));
if (note == null) return string.Empty;
return note.Substring(idString.Length, note.Length - (idString.Length + 1));

Answer 2

试

int StartIndex = notelist.IndexOf("'" + id.ToString() + ":");
string result = string.Empty;
if ( StartIndex >= 0 )
{
     string tempstr = notelist.SubString ( StartIndex + ("'" + id.ToString() + ":").Length );
     result = tempstr.SubString ( 0, tempstr.IndexOf ( "'" ) );
}

return result;

Answer 3

到目前为止，我了解您的代码，以下代码将为您提供解决方案

            string IdWithNote = string.Empty;
            string noteList = Properties.Settings.Default.FavoriteNotesList;//your string type note list
            List<string> listNote = new List<string>();//newly created string type collection
            listNote=noteList.Split(',').ToList<string>();

            int index=listNote.IndexOf("'" + id + ":");
            if (index > -1)
                IdWithNote = listNote[index];
            return IdWithNote;

Answer 4

老式的＆amp;清除（无正则表达式）还假设您只需要注释的文本，而不是整个注释结构。

string key = "'" + id + ":";
int noteStart = noteList.IndexOf(key);
if (noteStart >= 0)
{
    int textStart = noteStart + key.Length;
    int textEnd = noteList.IndexOf("'", textStart);
    return noteList.Substring(textStart, textEnd - textStart);
}
return "";

Answer 5

var myId=2;
var t="'1:note1','2:note2'";
var query = t.Split(',').Select(c => c.Replace("'", "").Split(':')).
                         Where(c => c[0] == myId.ToString()).
                         Select(p=>p[1]).First();

enter image description here

Answer 6

这里有一些代码 - 你真正想要的是：retVal = noteList.Substring（startIndex，endIndex - startIndex）;

        int id = 8;
        string noteList = "'8:the note i want','81:the note i do not want'";
        string toFind = "'" + id.ToString() + ":";
        int startIndex = noteList.IndexOf(toFind) + toFind.Length;
        int endIndex = noteList.IndexOf("'", startIndex);
        if (noteList.Contains(toFind))
        {
            retVal = noteList.Substring(startIndex, endIndex - startIndex);
        }
        else
        {
            retVal = "nothing found";
        }

Answer 7

notelist.Substring(notelist.IndexOf("'" + id + ":"), (notelist.IndexOf("'") - notelist.IndexOf("'" + id + ":")));

这应该可以做到，你可以通过子串将文本选择成新的字符串。 substring（startindex，lenght）;

从特定字符中选择字符串直到c＃中的某个字符

7 个答案: