How to get the JSON working with PHP - php

Question

I have the following code which pass data formatted as JSON to PHP through Ajax, but the PHP code doesn't print out the result.
var array_str_idnum = [];
for (var i=0;i<2;i++) {
array_str_idnum[i] = [];
}
$('#movetoset').click(function() {
if ($('#selectsett').val() === 'General') {
}
for(j=0;j< (array_str_idnum[0]).length;j++) {
if((document.getElementById('check' + array_str_idnum[0][j]).checked) && (array_str_idnum[1][j] != "moved")) {
document.getElementById('imagediv' + array_str_idnum[0][j]).style.display = 'none';
array_str_idnum[1][j] = "moved";
index = ((array_str_idnum[0]).length - 1 - j) + '';
var str = $("#complicated").serialize() + "&myindex=" + encodeURIComponent(index) ;
var desc_str = document.getElementById('textarea' + array_str_idnum[0][j]).value;
str = str + "&mydescription=" + encodeURIComponent(desc_str);
$.ajax({
type: "POST",
url: "addtoset.php",
data: str,
cache: false,
success: function(msg) {
$("#formstatus").ajaxComplete(function(){$(this).fadeIn("slow").html(msg + '<br /><br />')});
$("#formstatus").append(msg);
}
});
}
}
mydata = JSON.stringify(array_str_idnum);
$.ajax({
type: 'post',
cache: false,
url: 'parser.php',
data: {myJson: mydata},
success: function(msg) {
$("#formstatus").ajaxComplete(function() { $(this).fadeIn("slow").html(msg) });
}
});
});
Here is my PHP code:
$decoded = json_decode($_POST['myJson'],true);
// do something with data here
echo "decoded = $decoded[1][0]";
What's wrong with the code?

Answer 1

I think you want to fix your PHP code like others suggested, like so:
<?php
if ( !empty($_POST['myJson']) && strlen($_POST['myJson']) > 0 )
{
$decoded = json_decode( $_POST['myJson'], true );
// Echo out the JSON onject as a JavaScript variable.
echo "decoded = {$decoded[1][0]};";
}
else
{
// Echo out the JSON onject as a JavaScript variable.
echo "decoded = null;";
}
?>
Here is your JavaScript code with some minor suggestions:
<script type="text/javascript">
$( document ).ready(function()
{
var array_str_idnum = [];
// Init the array with two elemsnts that contain empty literal arrays.
for ( var i = 0; i < 2; i++ )
{
array_str_idnum[ i ] = [];
}
$( "#movetoset" ).click(function()
{
var $checkbox, str, desc_str, elementSuffix;
// I believe the code in here was removed for privacy reasons.
// I also believe it populats 'array_str_idnum' with some values of some kind.
if ( $("#selectsett").val() === "General" )
{
// ...
}
for ( var i = 0; i < (array_str_idnum[0]).length; i++ )
{
elementSuffix = array_str_idnum[ 0 ][ i ];
// Grab the checkbox.
$checkbox = $( "#check" + elementSuffix );
if ( $checkbox.checked && (array_str_idnum[1][i] != "moved") )
{
// Hide the image.
$( "#imagediv" + elementSuffix ).css({ "display": "none" });
// Indicate that this one is now moved, so do NOT process it again.
array_str_idnum[ 1 ][ i ] = "moved";
index = ( (array_str_idnum[0]).length - 1 - i ) + '';
// Setting str here will reinitialize it
str = $( "#complicated" ).serialize() + "&myindex=" + encodeURIComponent( index );
desc_str = $( "#textarea" + elementSuffix ).value;
str = str + "&mydescription=" + encodeURIComponent( desc_str );
// Bad idea to put ajax call in a loop.
$.ajax({
"type": "POST",
"url": "addtoset.php",
"data": str,
"cache": false,
"success": function( msg )
{
$( "#formstatus" ).ajaxComplete(function()
{
$( this ).fadeIn( "slow" ).html( msg + "<br /><br />" );
});
$( "#formstatus" ).append( msg );
}
});
}
}
mydata = JSON.stringify( array_str_idnum );
$.ajax({
"type": "POST",
"cache": false,
"url": "parser.php",
"data": { myJson: mydata },
"success": function( msg )
{
$( "#formstatus" ).ajaxComplete(function()
{
$( this ).fadeIn( "slow" ).html( msg )
});
}
});
});
});
</script>

Answer 2

Maybe your only problem is the echo statement. You'll have to change that to
echo "decoded = ".$decoded[1][0];
or
echo "decoded = {$decoded[1][0]}"; //
This is because PHP only notices "normal" variables in double-quoted strings. For array elements (or object properties) you'll have to use curly braces around the variable or use string concatenation.