如何在同一个wifi中获取其他设备的主机名？

Question

我找到了一些可以扫描本地网络并列出所有设备信息的iOS应用程序.

我好奇.

图:

Answer 1

第1步 - 凝胶本地IP

适用于iOS 7及更低版本

#include <ifaddrs.h>
#include <arpa/inet.h>

- (NSString *)getIPAddress {

    NSString *address = @"error";
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *temp_addr = NULL;
    int success = 0;
    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(&interfaces);
    if (success == 0) {
        // Loop through linked list of interfaces
        temp_addr = interfaces;
        while(temp_addr != NULL) {
            if(temp_addr->ifa_addr->sa_family == AF_INET) {
                // Check if interface is en0 which is the wifi connection on the iPhone
                if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) {
                    // Get NSString from C String
                    address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];

                }

            }

            temp_addr = temp_addr->ifa_next;
        }
    }
    // Free memory
    freeifaddrs(interfaces);
    return address;

} 

iOS 8

[[NSHost currentHost] address]

第2步 - 获取在线IP

https://github.com/tonymillion/Reachability
使用可访问性,您可以获得子网IP的可访问性.

Reachability* reach = [Reachability reachabilityWithHostname:subnetIp];

第3步 - 解析主机名

Apple有一篇很棒的文章,其中涵盖了HostnameResolving主题. https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/NetworkingTopics/Articles/ResolvingDNSHostnames.html

您也可以在iOS8中尝试更简单的变体

[[NSHost hostWithAddress:@"173.194.34.24"] name]

示例项目

https://github.com/mongizaidi/LAN-Scan
这是一个小项目,它执行局域网扫描,您只需要解析主机名,您将获得所需的结果.