thinkz ThinkZ

Nice answer on stackoverflow to the question of when to use one or the other content-types for POSTing data, viz. application/x-www-form-urlencoded and multipart/form-data.

“The moral of the story is, if you have binary (non-alphanumeric) data (or a significantly sized payload) to transmit, use multipart/form-data. Otherwise, use application/x-www-form-urlencoded.”

Matt Bridges' answer in full:

The MIME types you mention are the two Content-Type headers for HTTP POST requests that user-agents (browsers) must support. The purpose of both of those types of requests is to send a list of name/value pairs to the server. Depending on the type and amount of data being transmitted, one of the methods will be more efficient than the other. To understand why, you have to look at what each is doing

	<?php
	Header("Content-type:image/png");
	//定义header，声明图片文件，最好是png，无版权之扰;
	//生成新的四位整数验证码
	session_start();//开启session;
	$authnum_session = ’’;
	$str = ’ABCDE69FIJKLMNO78PVWXYZabcdeQRSTUfghijkmn3pqrstGHuvwxyz120’;
	//定义用来显示在图片上的数字和字母;
	$l = strlen($str); //得到字串的长度;
	//循环随机抽取四位前面定义的字母和数字;

	// Use Gists to store code you would like to remember later on
	console.log(window); // log the "window" object to the console