我想从 Swift 中的 DNS 查询中获取 IP 地址(如 192.168.0.1 或 87.12.56.50)。我用 100 种不同的方法尝试了 100 次……没有任何帮助,所以我不得不寻求帮助。 到目前为止,这是我的代码:
let host = CFHostCreateWithName(nil,"subdomain.of.stackoverflow.com").takeUnretainedValue();
CFHostStartInfoResolution(host, .Addresses, nil);
var success: Boolean = 0;
let addresses = CFHostGetAddressing(host, &success).takeUnretainedValue() as NSArray;
if(addresses.count > 0){
let theAddress = addresses[0] as NSData;
println(theAddress);
}
好的...这些是我尝试实现但未成功的代码的链接:
https://gist.github.com/mikeash/bca3a341db74221625f5
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最佳答案
您的代码将地址检索为“套接字地址”结构。
getnameinfo()
可用于将地址转换为数字 IP 字符串
(代码回收自 https://stackoverflow.com/a/25627545/1187415 ,
现在更新到 Swift 2):
let host = CFHostCreateWithName(nil,"www.google.com").takeRetainedValue()
CFHostStartInfoResolution(host, .Addresses, nil)
var success: DarwinBoolean = false
if let addresses = CFHostGetAddressing(host, &success)?.takeUnretainedValue() as NSArray?,
let theAddress = addresses.firstObject as? NSData {
var hostname = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
if getnameinfo(UnsafePointer(theAddress.bytes), socklen_t(theAddress.length),
&hostname, socklen_t(hostname.count), nil, 0, NI_NUMERICHOST) == 0 {
if let numAddress = String.fromCString(hostname) {
print(numAddress)
}
}
}
输出(示例):173.194.112.147
还要注意第一行中 takeRetainedValue()
的用法,因为
CFHostCreateWithName()
名称中有“Create”,因此返回 (+1) 保留
对象。
Swift 3/Xcode 8 更新:
let host = CFHostCreateWithName(nil,"www.google.com" as CFString).takeRetainedValue()
CFHostStartInfoResolution(host, .addresses, nil)
var success: DarwinBoolean = false
if let addresses = CFHostGetAddressing(host, &success)?.takeUnretainedValue() as NSArray?,
let theAddress = addresses.firstObject as? NSData {
var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
if getnameinfo(theAddress.bytes.assumingMemoryBound(to: sockaddr.self), socklen_t(theAddress.length),
&hostname, socklen_t(hostname.count), nil, 0, NI_NUMERICHOST) == 0 {
let numAddress = String(cString: hostname)
print(numAddress)
}
}
或者,获取主机的所有 IP 地址:
let host = CFHostCreateWithName(nil,"www.google.com" as CFString).takeRetainedValue()
CFHostStartInfoResolution(host, .addresses, nil)
var success: DarwinBoolean = false
if let addresses = CFHostGetAddressing(host, &success)?.takeUnretainedValue() as NSArray? {
for case let theAddress as NSData in addresses {
var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
if getnameinfo(theAddress.bytes.assumingMemoryBound(to: sockaddr.self), socklen_t(theAddress.length),
&hostname, socklen_t(hostname.count), nil, 0, NI_NUMERICHOST) == 0 {
let numAddress = String(cString: hostname)
print(numAddress)
}
}
}
关于swift - 如何从 Swift 中的 DNS 查询中获取真实 IP 地址?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/25890533/