Hi,
I’d like to start off by saying that I’m new here and would like to thank you for your help in advance. I’m new to PHP and AJAX, but has a small background and understanding of programming.
What I am trying to accomplish is to build a calculator. The user inputs a few parameters, hits a button and the result is outputted. The issue I’m having is that when I hit the button nothing happens and I get a POST 500 error (Internal Server Error).
I’ve tried everything and have no idea why this won’t work.
Here is my HTML code for the form
<div class="twelve columns">
<h2>Moment Resistance Using Strain-Stress Relationship</h2>
<form method="post" action="return.php" class="js-ajax-php">
<fieldset>
<legend>Step 1</legend>
<div class="row">
<div class="four columns">
<label for="fc">Concrete Compressive Strength - f'<sub>c</sub> [MPa]</label>
<input class="u-full-width" type="text" placeholder="e.g. 30" id="fc" name="fc">
</div>
<div class="four columns">
<label for="As">Reinforcing Bars Size - Tension</label>
<select class="u-full-width" id="As" name="As">
<option value="" disabled="" selected="">Select rebar size</option>
<option value="100">10M - 100 mm^2</option>
<option value="200">15M - 200 mm^2</option>
<option value="300">20M - 300 mm^2</option>
<option value="500">25M - 500 mm^2</option>
<option value="700">30M - 700 mm^2</option>
<option value="1000">35M - 1000 mm^2</option>
<option value="1500">45M - 1500 mm^2</option>
<option value="2500">55M - 2500 mm^2</option>
</select>
</div>
<div class="four columns">
<label for="bar-num">Number of Reinforcing Bars Per Row</label>
<input class="u-full-width" type="text" placeholder="e.g. 6" id="bar-num" name="bar-num">
</div>
</div>
<div class="row">
<div class="four columns">
<label for="fy">Steel Yield Strength - f<sub>y</sub> [MPa]</label>
<input class="u-full-width" type="text" name="fy" placeholder="e.g. 400" id="fy">
</div>
<div class="four columns">
<label for="b">Beam Width - b/b<sub>w</sub> [mm]</label>
<input class="u-full-width" type="text" name="b" placeholder="e.g. 300" id="b">
</div>
<div class="four columns">
<label for="h">Beam Height - h [mm]</label>
<input class="u-full-width" type="text" placeholder="e.g. 450" id="h" name="h">
</div>
</div>
<div class="row">
<div class="four columns">
<label for="bf">Flange Width - b<sub>f</sub> [mm]</label>
<input class="u-full-width" type="text" placeholder="e.g. 450" id="d" name="bf">
</div>
<div class="four columns">
<label for="hf">Flange Depth - h<sub>f</sub> [mm]</label>
<input class="u-full-width" type="text" placeholder="e.g. 450" id="hf" name="hf">
</div>
<!--
<div class="four columns">
<label for="c">C Value [mm]</label>
<input class="u-full-width" type="text" placeholder="e.g. 450" id="c" name="c">
</div>
-->
</div>
</fieldset>
<fieldset>
<legend>Step 2</legend>
<div class="row">
<div class="four columns">
<label for="ds">Effective Depth for Each Row - d<sub>s</sub> [mm]</label>
<input class="u-full-width" type="text" placeholder="e.g. 450" id="ds1" name="ds[]">
<input class="u-full-width" type="text" placeholder="e.g. 450" id="ds2" name="ds[]">
</div>
</div>
</fieldset>
<div class="row">
<div class="two columns">
<input class="button-primary" type="submit" value="Calculate">
</div>
<div class="two columns">
<input class="button-primary" type="reset" value="Reset">
</div>
<div class="four columns u-max-full-width">
<div class="the-return2">
<p>Moment Resistance:</p>
<p>0.00 kN.m <br />
The reinforcing steel …!</p>
</div>
</div>
</div>
</form>
</div> Here is the code for the PHP script:
[php]
<?php if (is_ajax()) { if (isset($_POST["action"]) && !empty($_POST["action"])) { //Checks if action value exists $action = $_POST["action"]; switch($action) { //Switch case for value of action case "test": test_function(); break; case "test2": new_function(); break; } } } //Function to check if the request is an AJAX request function is_ajax() { return isset($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest'; } //Moment Resistance using Strain-Stress Relationship function new_function(){ $return=$_POST; $fc = $_POST["fc"]; $fy = $_POST["fy"]; $b = $_POST["b"]; $h = $_POST["h"]; $bf = $_POST["bf"]; $hf = $_POST["hf"]; $ds = $_POST["ds"]; /* $c = $_POST["c"]; */ $c = 0; $alpha1 = 0.85 - 0.0015 * $fc; $beta1 = 0.97 - 0.0025 * $fc; $phis = 0.85; $phic = 0.65; $epsilonu = 0.0035; while ($c < 82) { for ($i = 0; $i < count($ds); $i++) { //Calculate strain in each layer of steel $epsilon[$i] = -$epsilonu * ($ds[$i] - $c) / $c; //Calculate stress in each layer of steel [MPa] if ($epsilon[$i] >= -0.002) { $fs[$i] = 200000 * $epsilon[$i]; } else { $fs[$i] = -380 + 10000 * $epsilon[$i]; } //Adjust Stress in Steel to yielding values if this occurs if ($fs[$i] > $fy) { $fs[$i] = $fy; } elseif ($fs[$i] < -$fy) { $fs[$i] = -$fy; } else { ; //Do nothing } //Calculate area of steel in each layer [mm2] $bar[$i] = $_POST["As"] * $_POST["bar-num"]; //Calculate the tension force in each layer of steel [kN] $Ts[$i] = $fs[$i] * $phis * $bar[$i] * pow(10,-3); } $Ts_Total = array_sum($Ts); //Calculate the compression force of the stress block [kN] $a = $beta1 * $c; $Cc[] = array(0,0,0); if ($a <= $hf) { $Cc[0] = $phic * $alpha1 * $fc * $a * $bf * pow(10,-3); } else { $Cc[1] = $phic * $alpha1 * $fc * $hf * ($bf - $b) * pow(10,-3); $Cc[2] = $phic * $alpha1 * $fc * $a * $b * pow(10,-3); } $Cc_Total = array_sum($Cc); $c = $c + 1; } //Calculate Mr [kN.m] $Mr[0] = ($Cc[0] * ($h/2 - $a/2) + $Cc[1] * ($h/2 - $hf/2) + $Cc[2] * ($h/2 - $a/2)) * pow(10,-3); //Mr for compressive stress for ($i = 0; $i < count($ds); $i++) { //Mr for tension stress $Mr[$i+1] = $Ts[$i] * ($h/2 - $ds[$i]) * pow(10,-3); } $Mr_Total = array_sum($Mr); $return["yield"] = "Yields"; $return["Mr"] = $Mr_Total; $return["Cc"] = $Cc_Total; $return["Ts"] = $Ts_Total; $return["c"] = $c-1; $return["a"] = $a; $return["json"] = json_encode($return); echo json_encode($return); } ?>[/php]
Here is the code for the AJAX:
$(".js-ajax-php").submit(function(){
var data = {
"action": "test2"
};
data = $(this).serialize() + "&" + $.param(data);
$.ajax({
type: "POST",
dataType: "json",
url: "script/response.php", //Relative or absolute path to response.php file
data: data,
success: function(data) {
$(".the-return2").html(
"<p>Moment Resistance:</p> "
+ "<p>" + data["Mr"].toFixed(2) + " kN.m"
+ "<br /> The reinforcing steel " + data["yield"] + "!</p>"
+ "<br />JSON: " + data["json"]
);
}
});
return false;
});
I just don’t understand why the code breaks as soon as I start using a while loop.
You can see a online version here: http://dev.gelias.ca
Any help will be greatly appreciated. Thank you.