Flex正則表達式找到url中兩個字符之間的匹配

Question

我在尋找一個正則表達式來解析a =和&之間的部分以獲得第一個url變量。

URL示例：

http://vandooren.be?v=123456&test=123 

我需要從字符串123456。

我最後的嘗試是

var pattern:RegExp = /\=|\&/; 
var result:Array = pattern.exec(dg.selectedItem.link[0]); 
trace(result.index, " - ", result); 

但我仍然得到錯誤。

Answer 1

請嘗試以下代碼。

var myPattern:RegExp = /(?<==).+(?=&)/; 
var str:String = "http://vandooren.be?v=123456&test=123"; 
var result:Array = myPattern.exec(str); 
trace(result[0]); //123456 

---

var myPattern:RegExp = /(?<==).+(?=&)/; 
var str:String = "youtube.com/watch?v=nCgQDjiotG0&feature=youtube_gdata"; 
var result:Array = myPattern.exec(str); 
trace(result[0]); //nCgQDjiotG0 

---

Assertions

foo(?=bar) Lookahead assertion. The pattern foo will only match if followed by a match of pattern bar. 
foo(?!bar) Negative lookahead assertion. The pattern foo will only match if not followed by a match of pattern bar. 
(?<=foo)bar Lookbehind assertion. The pattern bar will only match if preceeded by a match of pattern foo. 
(?<!foo)bar Negative lookbehind assertion. The pattern bar will only match if not preceeded by a match of pattern foo. 

Answer 2

試試這個：

(?<==)[^&]*(?=&) 

此正則表達式匹配無論是在「=」和前第一下一個「&」。