如何创建自定义NSCharacterSet？

Question

我正在使用CharacterSet.urlQueryAllowed百分比编码添加到字符串.

有些字符编码不希望我的方式(即&并?没有改变).话虽如此,我有了构建自定义的想法CharacterSet,理想情况是基于现有的自定义.

这样做的最佳方法是什么？

Answer 1

创建新字符集的最典型方法是使用 CharacterSet(charactersIn:),给出String该集合的所有字符.

使用以下命令可以为现有集添加一些字符:

let characterSet = NSMutableCharacterSet() //create an empty mutable set
characterSet.formUnionWithCharacterSet(NSCharacterSet.URLQueryAllowedCharacterSet())
characterSet.addCharactersInString("?&")

或者在Swift 3中简单地说:

var characterSet = CharacterSet.urlQueryAllowed
characterSet.insert(charactersIn: "?&")

对于URL编码,还要注意Objective-C和Swift URL编码

Answer 2

您可以尝试我的方法：

let password = "?+=!@#$%^&*()-_abcdABCD1234`~"

// Swift 2.3
extension NSCharacterSet {
    static var rfc3986Unreserved: NSCharacterSet {
        let mutable = NSMutableCharacterSet()
        mutable.formUnionWithCharacterSet(.alphanumericCharacterSet())
        mutable.addCharactersInString("-_.~")
        return mutable
    }
}

let encoding = password.stringByAddingPercentEncodingWithAllowedCharacters(.rfc3986Unreserved)

// Swift 3
extension CharacterSet {
    static var rfc3986Unreserved: CharacterSet {
        return CharacterSet(charactersIn: "-_.~").union(.alphanumerics)
    }
}

let encoding = password.addingPercentEncoding(withAllowedCharacters: .rfc3986Unreserved)

Print?
original -> ?+=!@#$%^&*()-_abcdABCD1234`~
encoding -> %3F%2B%3D%21%40%23%24%25%5E%26%2A%28%29-_abcdABCD1234%60~

rfc3986：https：//tools.ietf.org/html/rfc3986