iOS Swift操纵/parsingstring

我不知道如何在iOS Swift中做到这一点

let test = "fnfsjflsjlkdkfj?v=904kg4" // search test for ?v= and store everything after ?v= into a new string let newString = "904kg4" 

我想要一切后?v =成一个新的string,这可能吗? 如果是这样,我该如何做到这一点

使用rangeOfString查找?v=的范围,然后使用substringFromIndex获取string的其余部分:

 let test = "fnfsjflsjlkdkfj?v=904kg4" if let range = test.rangeOfString("?v=") { let newString = test.substringFromIndex(range.endIndex) }