Pass a C# struct with string to a C++ application -


i have c# struct pass via udp c++ application. checked length of string field , got different results c# , c++ codes. here definitions of structs:

//  c# side //------------- [structlayout(layoutkind.sequential, pack = 1)] public struct stname {  /// data types  [marshalas(unmanagedtype.byvaltstr, sizeconst = 20)]  string stringname; }  // c side //--------- struct stname{ /// data types char stringname[20];

when stringname = "192.168.53.2" size of field @ c# side 12 while 20 on c side. doing wrong? if c# uses actual length of string, field sizeconst stand for?

when check length of string in c#, counts number of characters (192.168.53.2 is, correctly, 12 characters long).

however, in c, string array of characters null-terminated. however, size of array in case set to, 20. size of "field" 20.

the sizeconst field refers size of c array, interop can create c array appropriately (with correct total size).


Comments

Post a Comment

Popular posts from this blog

javascript - Using jquery append to add option values into a select element not working -

i'm looking dynamically populate select element names of items stored array. for reason it's not working , i'm not sure why. html: <div class="col-md-4 col-md-offset-4"> <select class="select1"> </select> , <select class="select2"> </select> </div> note i'm using bootstrap layout. here's jquery i'm using try , populate ".select1" jquery: select: function() { $.each(state.greens, function(index, value) { $(".select1").append("<option value =' " + index + " '>" + state.greens[index].name + "</option>"); }); } note function 'select' stored within object called 'display'. state.greens name of array i'm trying access. so @ end of html page call display.select(); call function. no error messages showing in console. also, saw question: appending
Read more

Android soft keyboard reverts to default keyboard on orientation change -

i'm building android soft keyboard , can't seem fix bug - have arabic , qwerty keyboard , when rotate device on qwerty keyboard (or arabic shift), it's if program has "restarted" , becomes arabic keyboard without shift. the onsaveinstancestate(bundle savedinstancestate) not work because application not extend activity inputmethodservice . i put following in android manifest android:configchanges="keyboard|keyboardhidden|orientation" android:windowsoftinputmode="stateunchanged|adjustresize"> i tried using @override public void onconfigurationchanged(configuration newconfig) { super.onconfigurationchanged(newconfig); log.i(mydebug, "config changed " + currentkeyboard.equals(qwerty)); } however, currentkeyboard.equals(qwerty)) results false , made sure true before orientation change. any appreciated. i think applications fault. if application restarting on orientation change
Read more

jquery - javascript onscroll fade same class but with different div -

i new @ javascript , want learn new. there wrong code : why div fades @ same time. i want ask how fade different div s same class name.can me , explain me. thanks in advance. javascript: $(window).scroll(function(){ if ($( "div.fade" ).offset().top - $(window).scrolltop() <= 100){ $('.fade').addclass( "fade-in"); } else { $('.fade').removeclass("fade-in"); } }); here jsfiddle onscroll = function () { var scrolltop = $(this).scrolltop() ; $("div.fade").each(function(){ if(($(this).offset().top - scrolltop) <= 100){ $(this).toggleclass("fade-in"); } }) }
Read more