替换

把?替换为/

var url = "http://blog.csdn.net/hello_hwc?viewmode=list"
var filtered = url.stringByReplacingOccurrencesOfString("?",withString: "/",options: NSStringCompareOptions.LiteralSearch,range: nil)

结果

"http://blog.csdn.net/hello_hwc/viewmode=list"

过滤
过滤掉单个字符/
结果
过滤掉开头和结尾的空白

切割
对字符串使用/作为分隔符来切割，不允许空字符串
使用split函数
结果是一个数组

var url = "http://blog.csdn.net/hello_hwc?viewmode=list"
var filtered = url.stringByReplacingOccurrencesOfString("/",withString: "",range: nil)"http:blog.csdn.nethello_hwc?viewmode=list"var url = " http://blog.csdn.net/hello_hwc?viewmode=list "
var newString = url.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceCharacterSet())"http://blog.csdn.net/hello_hwc?viewmode=list"var url = "http://blog.csdn.net/hello_hwc?viewmode=list"
let splitedarray = split(url){$0 == "/"}"http:"
"blog.csdn.net"
"hello_hwc?viewmode=list"
 
拼接
let splitedarray = ["1","2","3"]
let result = join("/",splitedarray)"1/2/3"