上传文件时要设置为“multipart/form-data”是因为此类型不适合用于传输大型二进制数据或者包含非ASCII字符的数据。
Content-Type是什么?
Content-Type 实体头部用于指示资源的MIME类型 media type 。
在响应中,Content-Type标头告诉客户端实际返回的内容的内容类型。浏览器会在某些情况下进行MIME查找,并不一定遵循此标题的值; 为了防止这种行为,可以将标题 X-Content-Type-Options 设置为 nosniff。
Content-Type的句法示例:
Content-Type: text/html; charset=utf-8 Content-Type: multipart/form-data; boundary=something
为什么上传文件时要设置为“multipart/form-data”?
我们知道上传文件的时候media-type要设置为 multipart/form-data ,这是为什么呢?为什么不已有使用application/x-www-form-urlencoded呢?
因为此类型不适合用于传输大型二进制数据或者包含非ASCII字符的数据。平常我们使用这个类型都是把表单数据使用url编码后传送给后端,二进制文件当然没办法一起编码进去了。所以multipart/form-data就诞生了,专门用于有效的传输文件。
更多相关技术文章,请访问PHP中文网!

The article discusses PHP, detailing its full form, main uses in web development, comparison with Python and Java, and its ease of learning for beginners.

PHP handles form data using $\_POST and $\_GET superglobals, with security ensured through validation, sanitization, and secure database interactions.

The article compares PHP and ASP.NET, focusing on their suitability for large-scale web applications, performance differences, and security features. Both are viable for large projects, but PHP is open-source and platform-independent, while ASP.NET,

PHP's case sensitivity varies: functions are insensitive, while variables and classes are sensitive. Best practices include consistent naming and using case-insensitive functions for comparisons.

The article discusses various methods for page redirection in PHP, focusing on the header() function and addressing common issues like "headers already sent" errors.

Article discusses type hinting in PHP, a feature for specifying expected data types in functions. Main issue is improving code quality and readability through type enforcement.

The article discusses PHP Data Objects (PDO), an extension for database access in PHP. It highlights PDO's role in enhancing security through prepared statements and its benefits over MySQLi, including database abstraction and better error handling.

Article discusses creating and securing PHP APIs, detailing steps from endpoint definition to performance optimization using frameworks like Laravel and best security practices.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Zend Studio 13.0.1
Powerful PHP integrated development environment

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

SublimeText3 English version
Recommended: Win version, supports code prompts!
