尝试在 Swift 中解码 JWT 负载并遇到非常困难的时间
static func decodePayload(tokenstr: String) {
//splitting JWT to extract payload
let arr = split(tokenstr) {$0 == "."}
//base64 encoded string i want to decode
let base64String = arr[1] as String
println(base64String) //eyJleHAiOjE0MjY4MjIxNjMsImlkIjoiNTUwYjA3NzM4ODk1NjAwZTk5MDAwMDAxIn0
//attempting to convert base64 string to nsdata
let nsdata: NSData = NSData(base64EncodedString: base64String, options: NSDataBase64DecodingOptions(rawValue: 0))
//decoding fails because nsdata unwraps as nil
let base64Decoded: NSString = NSString(data: nsdata!, encoding: NSUTF8StringEncoding)!
}
最佳答案
eyJleHAiOjE0MjY4MjIxNjMsImlkIjoiNTUwYjA3NzM4ODk1NjAwZTk5MDAwMDAxIn0
不是有效的 Base64 编码字符串,因为它的长度
不是 4 的倍数。一些 Base64 解码器容忍这个错误,但是
NSData
方法没有。
所以这实际上是服务器端创建
Base64 编码的字符串。如有必要,您可以在您的应用程序中修复它
通过使用 =
字符添加所需的填充(针对 Swift 2 更新的代码):
var base64String = arr[1] as String
if base64String.characters.count % 4 != 0 {
let padlen = 4 - base64String.characters.count % 4
base64String += String(count: padlen, repeatedValue: Character("="))
}
现在解码工作正常:
if let data = NSData(base64EncodedString: base64String, options: []),
let str = String(data: data, encoding: NSUTF8StringEncoding) {
print(str) // {"exp":1426822163,"id":"550b07738895600e99000001"}
}
swift 4:
var base64String = "eyJleHAiOjE0MjY4MjIxNjMsImlkIjoiNTUwYjA3NzM4ODk1NjAwZTk5MDAwMDAxIn0"
if base64String.count % 4 != 0 {
let padlen = 4 - base64String.count % 4
base64String.append(contentsOf: repeatElement("=", count: padlen))
}
if let data = Data(base64Encoded: base64String) ,
let str = String(data: data, encoding: .utf8) {
print(str) // {"exp":1426822163,"id":"550b07738895600e99000001"}
}
关于ios - 在 Swift 中解码 JSON Web token ,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/29152706/