php filter_has_var 判断变量是否存在函数
定义和用法
该filter_has_var （ ）函数检查，如果一个变量指定输入类型存在。
在返回TRUE或FALSE成功的失败。
语法
filter_has_var(type, variable)
type |
|
| variable | 必需的。指定变量检查 |
例如 在这个例子中的输入变量“名称”发送到PHP页面：
<!--?phpif(!filter_has_var(INPUT_GET, "name")) { echo("Input type does not exist"); }else { echo("Input type exists"); }?-->
输出为.
Input type exists
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)
Dreamweaver CS6
Visual web development tools
WebStorm Mac version
Useful JavaScript development tools
PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
