SimpleXMLElement::__construct(): Entity: line 1: parser error : Start tag expected, '<' not found

Question

The code below (using CodeIgniter 3.0) is giving this error, and I don't understand why:

SimpleXMLElement::__construct(): Entity: line 1: parser error : Start tag expected, '<' not found

<?php

require_once './pdfGenerator.php';
require_once './pdfWrapper.php';
require_once './tcpdf_ext.php';
$debug = false;
$error_handler = set_error_handler("PDFErrorHandler");

if (get_magic_quotes_gpc()) {
    $xmlString = stripslashes($_POST['mycoolxmlbody']);
} else {
    $xmlString = $_POST['mycoolxmlbody'];
}
//where the problem

if ($debug == true) {
    error_log($xmlString, 3, 'debug_'.date("Y_m_d__H_i_s").'.xml');
}

$xml = new SimpleXMLElement($xmlString, LIBXML_NOCDATA);
$scPDF = new schedulerPDF();
$scPDF->printScheduler($xml);
function PDFErrorHandler ($errno, $errstr, $errfile, $errline) {
    global $xmlString;
    if ($errno < 1024) {
        echo $errstr."<br>";
        error_log($xmlString, 3, 'error_report_'.date("Y_m_d__H_i_s").'.xml');
        exit(1);
    }
}

Answer 1

use

$xml = simplexml_load_string($xmlString,'SimpleXMLElement', LIBXML_NOCDATA);

instead of

$xml = new SimpleXMLElement($xmlString,LIBXML_NOCDATA);