Content-Type Header

Hii ni aina ya header abayo inatoa taarifa kwenye device ya client kuhusu maudhui (content) yanayotumwa kutoka kwenye http header. Hii ni muhimu kwa sababi kila content inakuna na namna yake jinsi ya kuitumia. Browser zinahitaji kueewa aina ya contente hiyo. Kama ni video, html, image, pdf na zaidi.

Ili kuweza kuangalia ama kutumia content header utatumia header() function. Ndani yake utaweka utaweka keyword Content-Type ambapo kitaalamu inaitwa HTTP header field itafiatailwa na value za hiyo field. Mfano kama ni html itaandikwa header('Content-Type: text/html') tutajifunza zaidi hapo mbele.

Content type headers zinaweza kuwa:-

Html document hii huwakilishwa kwa header('Content-Type: text/html')
JSON Data huwakilishwa kwa header('Content-Type: application/json');
Plain text huwakilishwa kwa header('Content-Type: text/plain');
XML Data huwakilishwa kwa header('Content-Type: application/xml');
Form Data huwakilishwa kwa header('Content-Type: application/x-www-form-urlencoded'); kama ni njia ya post. Na kama Ndani ya form hiyo kuna faili ambalo linakwenda kuwa uploaded, tutatumia header('Content-Type: multipart/form-data');
Images huwakilishwa kwa header('Content-Type: image/jpeg');

header('Content-Type: image/png'); utaongeza aina ya picha husika.

Kwa taarifa za content yinginezo kama pdf, javascript na zaidi ya hapo utatumia tu header('Content-Type: application/aina ya faili'); mfano header('Content-Type: application/zip');
Video na audio ni kama huwakilishw akwa header('Content-Type: video/mp4'); au header('Content-Type: audio/mpeg');

Unaweza kurejea somo lililotangulia kuifunza jinsi ya kupata taarifa za header. Kisha tumia somo hili ili kuweza kujuwa aina ya content ambayo ipo kwneye hilo faili.

Mfano zaidi:

<?php

// HTML Content

header('Content-Type: text/html');

echo "<h1>Hii ni HTML Content</h1>";

// JSON Data

header('Content-Type: application/json');

echo json_encode(["message" => "Hii ni JSON Data"]);

// Plain Text

header('Content-Type: text/plain');

echo "Hii ni Plain Text";

// XML Data

header('Content-Type: application/xml');

echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?><message>Hii ni XML Data</message>";

// Form Data

header('Content-Type: application/x-www-form-urlencoded');

echo "field1=value1&field2=value2";

// Multipart Form Data (for file upload)

header('Content-Type: multipart/form-data');

echo "--boundary\r\nContent-Disposition: form-data; name=\"field1\"\r\n\r\nvalue1\r\n--boundary\r\nContent-Disposition: form-data; name=\"file\"; filename=\"file.txt\"\r\nContent-Type: text/plain\r\n\r\nFile content goes here\r\n--boundary--";

// Image JPEG

header('Content-Type: image/jpeg');

// Output an actual JPEG image here

// Image PNG

header('Content-Type: image/png');

// Output an actual PNG image here

// PDF File

header('Content-Type: application/pdf');

// Output an actual PDF file here

// JavaScript

header('Content-Type: application/javascript');

echo "console.log('Hii ni JavaScript');";