c# - Why i'm getting exception No connection could be made when trying to send data to a server? -

this method:

private void senddatatoserver()         {             webrequest request = webrequest.create("http://10.0.0.2:8080 ");             request.method = "post";             string postdata = "this test posts string web server.";             byte[] bytearray = encoding.utf8.getbytes(postdata);             request.contenttype = "application/x-www-form-urlencoded";             request.contentlength = bytearray.length;             stream datastream = request.getrequeststream();             datastream.write(bytearray, 0, bytearray.length);             datastream.close();             webresponse response = request.getresponse();             console.writeline(((httpwebresponse)response).statusdescription);             datastream = response.getresponsestream();             streamreader reader = new streamreader(datastream);             string responsefromserver = reader.readtoend();             console.writeline(responsefromserver);             reader.close();             datastream.close();             response.close();         } 

1. maybe port 8080 didn't use right ?

2. the string should send server should in format:

   "http://10.0.0.2:8080/?say=hello world"

   the same when type in chrome browser when type: http://10.0.0.2:8080/?say=hello world

the part http://10.0.0.2:8080/?say= should never change. text after hello world if change hello or else. left part http://10.0.0.2:8080/?say= should never change.

the exception on line:

stream datastream = request.getrequeststream(); 

no connection made because target machine actively refused it

i checked in chrome can send hello world: http://10.0.0.2:8080/?say=hello world

http post messages can include body, block of data, in example postdata variable sent body of message.

besides block of data, can send query string, number of key/value pairs included in request uri, in form ?key1=value1&key2=value2.

the server can choose process either query string, body, or both, , server you're communicating chooses process query string.

however error message "no connection made because target machine actively refused it" more caused space character added request uri: "http://10.0.0.2:8080 ".