Gform pre render

Description

This filter is executed before the form is displayed and can be used to manipulate the Form Object prior to rendering the form.

Usage

<?php
add_filter("gform_pre_render", "pre_render_function");
?>

You can also specify this per form by adding the form id after the hook name.

<?php
add_filter("gform_pre_render_6", "pre_render_function");
?>

Parameters

$form

(Form Object) The current Form Object to be filtered.

Examples

This example dynamically populates a drop down field with posts that are in the Business category.

<?php
add_filter("gform_pre_render", "populate_dropdown");

//Note: when changing drop down values, we also need to use the gform_admin_pre_render so that the right values are displayed when editing the entry.
add_filter("gform_admin_pre_render", "populate_dropdown");

function populate_dropdown($form){

    //only populating drop down for form id 5
    if($form["id"] != 5)
       return $form;

    //Reading posts for "Business" category;
    $posts = get_posts("category=" . get_cat_ID("Business"));

    //Creating drop down item array.
    $items = array();

    //Adding initial blank value.
    $items[] = array("text" => "", "value" => "");

    //Adding post titles to the items array
    foreach($posts as $post)
        $items[] = array("value" => $post->post_title, "text" => $post->post_title);

    //Adding items to field id 8. Replace 8 with your actual field id. You can get the field id by looking at the input name in the markup.
    foreach($form["fields"] as &$field)
        if($field["id"] == 8){            
            $field["choices"] = $items;
        }

    return $form;
}
?>

The following example dynamically populates a checkbox field with a list of published posts

//NOTE: update the '221' to the ID of your form
add_filter('gform_pre_render_221', 'populate_checkbox');
add_filter("gform_pre_submission_filter_221", "populate_checkbox");

function populate_checkbox($form){

    foreach($form['fields'] as &$field){

        //NOTE: replace 3 with your checkbox field id
        $field_id = 3;
        if($field['id'] != $field_id)
            continue;

        // you can add additional parameters here to alter the posts that are retreieved
        // more info: http://codex.wordpress.org/Template_Tags/get_posts
        $posts = get_posts('numberposts=-1&post_status=publish');

        $input_id = 1;
        foreach($posts as $post){

            //skipping index that are multiples of 10 (multiples of 10 create problems as the input IDs)
            if($input_id % 10 == 0)
                $input_id++;

            $choices[] = array('text' => $post->post_title, 'value' => $post->post_title);
            $inputs[] = array("label" => $post->post_title, "id" => "{$field_id}.{$input_id}");

            $input_id++;
        }

        $field['choices'] = $choices;
        $field['inputs'] = $inputs;

    }

    return $form;
}

This example is for a two-page form. The data submitted from the first page is displayed on the second page as a preview. The second page has only one field, an html field that will be populated with the data from the first page.

<?php
add_filter("gform_pre_render_31", "populate_html");
function populate_html($form)
{
	//this is a 2-page form with the data from page one being displayed in an html field on page 2
	$current_page = GFFormDisplay::get_current_page($form["id"]);
	$html_content = "The information you have submitted is as follows:<br/><ul>";
	if ($current_page == 2)
	{
		foreach($form["fields"] as &$field)
		{
			//gather form data to save into html field (id 3 on my form), exclude page break
			if ($field["id"] != 3 && $field["type"] != "page")
			{
				//see if this is a complex field (will have inputs)
				if(rgar($field, "inputs"))
				{
					//this is a complex fieldset (name, adress, etc.) - get individual field info
					foreach($field["inputs"] as $input){
						//get name of individual field, replace period with underscore when pulling from post
						$input_name = "input_" . str_replace(".","_",$input["id"]);
						$value = rgpost($input_name);
						$html_content .= "<li>" . $input["label"] . ": " . $value . "</li>";
					}
				}
				else
				{
					//this can be changed to be a switch statement if you need to handle each field type differently
					//get the filename of file uploaded or post image uploaded
					if ($field["type"] == "fileupload" || $field["type"] == "post_image")
					{
						$input_name = "input_" . $field["id"];
						//before final submission, the image is stored in a temporary directory
						//if displaying image in the html, point the img tag to the temporary location
						$temp_filename = RGFormsModel::get_temp_filename($form["id"], $input_name);
						$uploaded_name = $temp_filename["uploaded_filename"];
						$temp_location = RGFormsModel::get_upload_url($form["id"]) . "/tmp/" . $temp_filename["temp_filename"];
						if (!empty($uploaded_name)) {
							$html_content .= "<li>" . $field["label"] . ": " . $uploaded_name . "<img src='" . $temp_location . "' height='200' width='200'></img></li>";
						}	
					}
					else
					{	
						//get the label and then get the posted data for the field (this works for simple fields only - not the field groups like name and address)
						$html_content .= "<li>" . $field["label"] . ": " . rgpost('input_' . $field['id']) . "</li>";
					}
				}	
			}
		}
		$html_content .= "</ul>";
		//loop back through form fields to get html field (id 3 on my form) that we are populating with the data gathered above
		foreach($form["fields"] as &$field)
		{
			//get html field
			if ($field["id"] == 3)
			{
				//set the field content to the html
				$field["content"] = $html_content;
			}
		}
	}
	//return altered form so changes are displayed
	return $form;		
}
?>

Placement

This code should be placed in the functions.php file of your active theme.

Source Code

This filter is located in form_display.php