HTML JS on iOS lazarus / 38-Networking and Web Programming ---------------------------------------------------------------------- epergola · 2020-12-15 15:35 I hope ther is someone expert on this topic. I have this code. It works fine in Android Chrome. In iOS resp shows "undefined". async function submitfuncR(resp,saveterminal){    alert(resp);   THIS SHOWS "UNDEFINED" in iOS    ............ } async function submitfunc(submitfuncR) {     var xhr = new XMLHttpRequest;     xhr.onreadystatechange=function(){       if (xhr.readyState === 4 && (xhr.status ===200 ) {          ...........         resp=xhr.response;         submitfuncR(resp,saveterminal);       }     }     xhr.open("POST",_serverpar,true);     xhr.send("login;");     return false; } It is called in the body section like this: ---------------------------------------------------------------------- lainz · 2020-12-15 23:51 Try evaluating resp = xhr.response, if is undefined or not before you send it to submitfuncR ---------------------------------------------------------------------- epergola · 2020-12-16 19:02 Thanks Lainz. Of course I did. It does show xhr.response just before the call to submitR, but it shows undefined in the first line of that function. I repat shows ok in Android Chrome, but it fails on iOS Chrome. ---------------------------------------------------------------------- lainz · 2020-12-17 01:28 Cross plataform bugs  even in the web... What if you make a real copy of the response? Or just the data you need to see and pass that? Edit: I said that because I don't know the data type of the response. Also I noticed that you forget to put var before resp assignment. Not sure if that does something on iOS. Like by default strict mode or something...