Question

所以我试图将一些obj-c代码转换为swift，但我仍然坚持使用它的一部分。我如何在swift中做这样的事情？

- (void)sometMethod:(NSString *)s {
NSString * crlfString = [s stringByAppendingString:@"\r\n"];
uint8_t *buf = (uint8_t *)[crlfString UTF8String];}

真正的问题是这一行

uint8_t *buf = (uint8_t *)[crlfString UTF8String];

Answer 1

你想用UTF-8缓冲区做什么？通常，将字符串直接转换为NSData对象会更方便。但是你也可以将你的Obj-C代码逐个翻译成Swift。以下是两种变体：

import Foundation

func appendCRLFAndConvertToUTF8_1(s: String) -> NSData {
    let crlfString: NSString = s.stringByAppendingString("\r\n")
    let buffer = crlfString.UTF8String
    let bufferLength = crlfString.lengthOfBytesUsingEncoding(NSUTF8StringEncoding)
    let data = NSData(bytes: buffer, length: bufferLength)
    return data;
}

func appendCRLFAndConvertToUTF8_2(s: String) -> NSData {
    let crlfString = s + "\r\n"
    return crlfString.dataUsingEncoding(NSUTF8StringEncoding)!
}

let s = "Hello "
let data1 = appendCRLFAndConvertToUTF8_1(s)
data1.description

let data2 = appendCRLFAndConvertToUTF8_2(s)
data2.description

data1 == data2

如果您想迭代UTF-8代码单元而不处理缓冲区，请使用以下内容：

for codeUnit in String.utf8 {
    println(codeUnit) 
}

obj -c到Swift转换代码

1 个答案: