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JavaScript AJAX Basics (retiring) Programming AJAX Processing JSON Data

i don't know what is wrong with my code on this exemplo .

var xhr = new XMLHttpRequest(); xhr.onreadystatechange = function (){ if (xhr.readyState === 4) { var employees = JSON.parse(xhr.responseText); var statusHTML = '<lu class="bulleted">'; for (var i = 0; i < employees.length; i =+ 1) { if (employees[i].inoffice === true){ statusHTML += '<li class="in">'; }else{ statusHTML += '<li class="out">'; } statusHTML += employees[i].name; //the error is here: Uncaught RangeError: Invalid string length statusHTML += '</li>'; } statusHTML += '</ul>'; document.getElementById('employeeList').innerHTML = statusHTML; } }; xhr.open('GET', 'data/employees.json'); xhr.send();

3 Answers

Steven Parker
Steven Parker
231,236 Points

It looks like your loop keeps adding on to the "statusHTML" variable until it exceeds the maximum length. Your "for" statement has a couple of characters transposed which makes the loop go on forever (or until error):

    for (var i = 0; i < employees.length; i = +1) {  // you probably want "i += 1" instead here

I need a new glasses :-)

Steven Parker
Steven Parker
231,236 Points

Something like a "non-terminating loop" might not be what you intended, but it's not actually a program error from the viewpoint of the language itself.

I believe some IDE's have a facility to detect and interrupt a program that is looping very quickly, but I don't think the workspace does. But your browser may have debugging features that allow you to manually interrupt a program and to set breakpoints to occur when things (like too many iterations) occur.