how to send data from iphone over wifi to application, to print message

i would like to know how to do the following:

step 1: how to send the following string from the iphone to a mac computer via WIFI when a user presses a button.

string to be sent: "hello"开发者_如何转开发.

step2: how to receive that string with an application i would have to create. it will be very simple. it will have no interface, except it will just print out the message.

How do i achieve something like this. I've never sent a signal over WIFI with the iphone programming. Can someone guide me please?

I'll quote myself from a similar question:

How can I create a small Mac app that receives data over the WiFi network from an iOS app?

Using the CFNetwork framework, you can use bonjour for discovery and then handle a persistent connection through native sockets for passing data back and forth.

http://developer.apple.com/library/ios/#documentation/Networking/Conceptual/CFNetwork/Introduction/Introduction.html

Here is an excellent tutorial to get started, its for iOS but CFNetwork is available in OS X too.

http://mobileorchard.com/tutorial-networking-and-bonjour-on-iphone

If by "wifi", you mean "local network", this blog post has some sample code that has an iPhone app and Mac application communicating via Bonjour. It does a bit more that what you're asking for, but it's something that will get you started.

If by "wifi", you mean "the Internet", you're going to need your own server sitting between the two devices. This is significantly more complex, but still doable, and you'll need to implement the server portion in whatever you're preferred server side technology is.