$re = '/"[^"{}]+":\s*{[^{}]*"_href":[^{}]*}/m';
$str = '[{
"name": "Test",
"junkAttributeA": {
"_href": "string",
"_type": "string"
},
"junkAttributeB": {
"_href": "string",
"_type": "string"
}
}]';
$subst = "";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php