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I am trying to make my form work, but keep getting this error. I have uploaded it to a server, but its just not working. What am I doing wrong? This is the error message I am getting:
Fatal error: Call to undefined function curl_init() in /home/mxwll05/public_html/beta/MSY/test-contact/Contact.php on line 82
PLEASE HELP! Here's my code for contact.php
<?php
/*
 * Copyright 2008, Constant Contact
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

class Contact {
        // Constructor VARIABLES
    var $user_name;
    var $password;
    var $api_key;
    var $log_file_name = "ccsub.log";
    // contact vars
    var $email_address='';
    var $list_url;
    var $first_name;
    var $last_name;
    var $middle_name;
    var $company_name;
    var $job_title;
    var $work_phone;  
    var $home_phone;
    var $update_date;
    var $list_name;
    var $err_message;
    var $custom_fields = array();
    var $nritems;
// FUNCTIONS
// constructor
    public function __construct($user,$pw,$key, $log_file) {
        $this->user_name=$user;
        $this->password=$pw;
        $this->api_key=$key;
        if ($log_file) $this->log_file_name=$log_file;
    }  
    // set contact vars
    function SetPrimaryInfo($email, $list, $first, $last, $middle, $company, $job) {
            //if ((!empty($email)) && (eregi('^[a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.([a-zA-Z]{2,4})$', $email))) {
            //    $this->err_message .= '<br />Missing or invalid email address.';
            //}
        $this->email_address=$email;
        $this->first_name=$first;
        $this->last_name=$last;
        $this->middle_name=$middle;
        $this->update_date=date("Y-m-d").'T'.date("H:i:s").'+01:00';
        $this->company_name=$company;
        $this->job_title=$job;
        $this->list_name=$list;
        $this->list_url=$this->FindContactList($list);
    }

    public function SetContactInfo($home_num, $home_num, $addr_1, $addr_2, $addr_3, $city, $state, $country, $postal_code, $sub_postal) {
        $this->home_number=$home_num;
        $this->home_number=$home_num;
        $this->address_line_1=$addr_1;
        $this->address_line_2=$addr_2;
        $this->address_line_3=$addr_3;
        $this->city_name=$city;
        $this->state_code=$state;
        $this->country_code=$country;
        $this->zip_code=$postal_code;
        $this->sub_zip_code=$sub_postal;
    }

        public function SetCustomFields($cf_array) {
                    $this->custom_fields = $cf_array;
        }

        private function FindContactList($list_name) {
        $request =  "http://api.constantcontact.com/ws/customers/".$this->user_name."/lists";
        $session = curl_init($request);
          // Set up Digest authentication - username and password.
        $userNamePassword = $this->api_key."%".$this->user_name.":".$this->password;
        if (empty($this->api_key) || empty($this->user_name) || empty($this->password)) {
            $this->err_message  .= '<br />Missing or invalid user name or password or api key.';
            error_log(date('Y-m-d H:i:s') .
                               ' Error invlid user name or password or api key '.
                               "\n", 3, $this->log_file_name);           
        }
        curl_setopt($session, CURLOPT_HTTPAUTH, CURLAUTH_DIGEST);
        curl_setopt($session, CURLOPT_USERPWD, $userNamePassword);
        curl_setopt($session, CURLOPT_FOLLOWLOCATION  ,1);
        curl_setopt($session, CURLOPT_GET, 1);
        curl_setopt($session, CURLOPT_HTTPHEADER, Array("Content-Type:application/atom+xml"));
        curl_setopt($session, CURLOPT_HEADER, 0);   // Do not return headers
        //don't send the response to browser
                 curl_setopt($session, CURLOPT_RETURNTRANSFER, 1);
        $response = curl_exec($session);
        curl_close($session);
                //error handling and write to log file
        if (!$response) {
            $list_id = -1;
                    if ($this->log_file_name) error_log(date('Y-m-d H:i:s') .
                               ' Error attempting to connect via curl to ' . $request .
                               "\n", 3, $this->log_file_name);           
        } else {
            $data = simplexml_load_string($response);
                    foreach($data->entry as $data_entry) {
                $entry_name = urlencode($data_entry->content->ContactList->Name);
                if ($entry_name == $list_name) {
                    $list_id=$data_entry->content->ContactList['id'];
                  }
                }
                }
        return $list_id;
        }

        public function GetErrorMessage() {
            return $this->err_message;
        }
    // output feed
    public function MaketEntry() {
            if ($this->list_url == -1 || empty($this->list_url) || $this->list_url == ""){
                    $this->err_message .= '<br />could not find valid list with the name '. $this->list_name;
                    error_log(date('Y-m-d H:i:s') .
                               ' Error could not find valid list with list name ' . $this->list_name .
                               "\n", 3, $this->log_file_name);
            }
        $xml_sttring = "<entry xmlns='http://www.w3.org/2005/Atom'></entry>";
           
            $xml_object = simplexml_load_string($xml_sttring);

            $title_node = $xml_object->addChild("title", htmlspecialchars("Hmmm this is ignored right now"));
            $updated_node = $xml_object->addChild("updated", htmlspecialchars($this->update_date));
            $author_node = $xml_object->addChild("author");
            $author_name = $author_node->addChild("name", htmlspecialchars("CTCT Samples"));
            $id_node = $xml_object->addChild("id", "urn:uuid:E8553C09F4xcvxCCC53F481214230867087");

            $summary_node = $xml_object->addChild("summary", htmlspecialchars("Customer document"));
            $summary_node->addAttribute("type", "text");
            $content_node = $xml_object->addChild("content");
            $content_node->addAttribute("type", "application/vnd.ctct+xml");

           
            $contact_node = $content_node->addChild("Contact", htmlspecialchars("Customer document"));
            $contact_node->addAttribute("xmlns", "http://ws.constantcontact.com/ns/1.0/");
            $email_node = $contact_node->addChild("EmailAddress", urldecode(htmlspecialchars($this->email_address)));
            $fname_node = $contact_node->addChild("FirstName", urldecode(htmlspecialchars($this->first_name)));
            $lname_node = $contact_node->addChild("LastName", urldecode(htmlspecialchars($this->last_name)));
            $lname_node = $contact_node->addChild("MiddleName", urldecode(htmlspecialchars($this->middle_name)));
            $lname_node = $contact_node->addChild("CompanyName", urldecode(htmlspecialchars($this->company_name)));
            $lname_node = $contact_node->addChild("JobTitle", urldecode(htmlspecialchars($this->job_title)));
            $optin_node = $contact_node->addChild("OptInSource", htmlspecialchars("ACTION_BY_CONTACT"));
        if (!empty($this->home_number))
                $hn_node = $contact_node->addChild("HomePhone", htmlspecialchars($this->home_number));
        if (!empty($this->work_number))
                $wn_node = $contact_node->addChild("WorkPhone", htmlspecialchars($this->work_number));
        if (!empty($this->address_line_1))
                $ad1_node = $contact_node->addChild("Addr1", htmlspecialchars($this->address_line_1));
        if (!empty($this->address_line_2))
                $ad2_node = $contact_node->addChild("Addr2", htmlspecialchars($this->address_line_2));
        if (!empty($this->address_line_3))
                $ad3_node = $contact_node->addChild("Addr3", htmlspecialchars($this->address_line_3));
        if (!empty($this->city_name))
                $city_node = $contact_node->addChild("City", htmlspecialchars($this->city_name));
        if (!empty($this->state_code))
                $state_node = $contact_node->addChild("StateCode", htmlspecialchars($this->state_code));
        if (!empty($this->country_code))
                $ctry_node = $contact_node->addChild("CountryCode", htmlspecialchars($this->country_code));
        if (!empty($this->zip_code))
                $zip_node = $contact_node->addChild("PostalCode", htmlspecialchars($this->zip_code));
        if (!empty($this->sub_zip_code))
                $subzip_node = $contact_node->addChild("SubPostalCode", htmlspecialchars($this->sub_zip_code));
        if (!empty($this->custom_fields)) {
            foreach($this->custom_fields as $k=>$v) {
                if (!empty($v))
                    $contact_node->addChild("CustomField".$k, htmlspecialchars($v));
            }
        }
                $contactlists_node = $contact_node->addChild("ContactLists");
            $contactlist_node = $contactlists_node->addChild("ContactList");
            $contactlist_node->addAttribute("id", $this->list_url);

                $entry = $xml_object->asXML();
        return $entry;
    }
};
?>