Question

我有一个字符串

“奥兰多，奥兰多国际机场（MCO），美国” 我想得到的代码只有MCO 如果string不包含代码，则返回null

寻找可以在一行中执行的linq查询

Answer 1

       var value = "Orlando, Orlando International Airport(MCO), United States";
       var result = from p in value.Split(',')
                    let flg = p.IndexOf("(MCO)") > -1
                    select flg ? p : null;

Answer 2

我更喜欢正则表达式。看我的例子：

string resultString = null;
try
{
    string part = "Orlando, Orlando International Airport(MCO), United States";
    resultString = Regex.Match(part, @"(?<=\().*(?=\))", RegexOptions.IgnoreCase | RegexOptions.Multiline).Value;
}
catch (ArgumentException ex)
{
    // Syntax error in the regular expression
}

对于表达式的文档：

// (?<=\().*(?=\))
// 
// Options: case insensitive; ^ and $ match at line breaks
// 
// Assert that the regex below can be matched, with the match ending at this position (positive lookbehind) «(?<=\()»
//    Match the character “(” literally «\(»
// Match any single character that is not a line break character «.*»
//    Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»
// Assert that the regex below can be matched, starting at this position (positive lookahead) «(?=\))»
//    Match the character “)” literally «\)»

C＃条件Linq查询以获取括号内的值

2 个答案: