c# - 多个级别的特殊字符串模式的正则表达式

Question

我需要评估一个类似于下面给出的字符串模式，我对编写这种复杂的表达式很陌生

<%(ddlValue){DropDownList}[SelectedValue]%>
// this has three part (Control Name) {Control Type} [Control Property]

我尝试了很多正则表达式和其他工具，例如 RegExr，但都没有用。我必须在四个级别上执行此操作，如下面的代码所示。所以这就是我所做的:

string regex = "/[<%](.*?)[%>]/g"; // Regex to match "<% %>" pattern
Match mtch = Regex.Match(strQuery, regex, RegexOptions.Singleline);
    string strControlName = "";
    string strControlType = "";
    string strControlProp = "";
    if (mtch.Success)
    {
        string strVal = mtch.Value;
        Match mtchControlName = Regex.Match(strVal, "/[(]\S)/"); 
        // Regex to match "()" i.e. control name ("ddlValue" in above example)
        if (mtchControlName.Success)//Match control Name
        {
            strControlName = mtchControlName.Value;
            Match mtchControlType = Regex.Match(strVal, "/[{]\s[}]/"); 
            // Regex to match "[]" i.e. control type
            if (mtchControlType.Success) // Match Control Type
            {
                strControlType = mtchControlType.Value;
                Match mtchControlProp = Regex.Match(strVal, "/[(]\S[)]/"); 
                // Regex to match "[]" i.e. control property
                if (mtchControlProp.Success) // Match Control Prop
                {
                     strControlProp = mtchControlProp.Value;
                }
             }
         }
     }

Answer 1

您可以在单个正则表达式中执行此操作。尽可能具体，你可以这样做:

Regex regexObj = new Regex(
    @"\(           # Match (
    (              # Capture in group 1:
     [^()]*        # Any number of characters except ()s
    )              # End of group 1
    \)             # Match )
    \{([^{}]*)\}   # The same for {...} into group 2
    \[([^\[\]]*)\] # The same for [...] into group 3", 
    RegexOptions.IgnoreCase | RegexOptions.IgnorePatternWhitespace);

然后你用例

Match matchResults = regexObj.Match(subjectString);

获取 Match 对象。通过

访问子匹配

matchResults.Groups(n).Value   // insert 1, 2 or 3 for n

查看live on regex101.com .