下载
文档
参与其中
帮助
PHP 8.3.0 RC 6 available for testing
Getting Started
Introduction
A simple tutorial
Language Reference
Basic syntax
Types
Variables
Constants
Expressions
Operators
Control Structures
Functions
Classes and Objects
Namespaces
Enumerations
Errors
Exceptions
Fibers
Generators
Attributes
References Explained
Predefined Variables
Predefined Exceptions
Predefined Interfaces and Classes
Predefined Attributes
Context options and parameters
Supported Protocols and Wrappers
Security
Introduction
General considerations
Installed as CGI binary
Installed as an Apache module
Session Security
Filesystem Security
Database Security
Error Reporting
User Submitted Data
Hiding PHP
Keeping Current
Features
HTTP authentication with PHP
Cookies
Sessions
Dealing with XForms
Handling file uploads
Using remote files
Connection handling
Persistent Database Connections
Command line usage
Garbage Collection
DTrace Dynamic Tracing
Function Reference
Affecting PHP's Behaviour
Audio Formats Manipulation
Authentication Services
Command Line Specific Extensions
Compression and Archive Extensions
Cryptography Extensions
Database Extensions
Date and Time Related Extensions
File System Related Extensions
Human Language and Character Encoding Support
Image Processing and Generation
Mail Related Extensions
Mathematical Extensions
Non-Text MIME Output
Process Control Extensions
Other Basic Extensions
Other Services
Search Engine Extensions
Server Specific Extensions
Session Extensions
Text Processing
Variable and Type Related Extensions
Web Services
Windows Only Extensions
XML Manipulation
GUI Extensions
Keyboard Shortcuts
?
This help
j
Next menu item
k
Previous menu item
g p
Previous man page
g n
Next man page
G
Scroll to bottom
g g
Scroll to top
g h
Goto homepage
g s
Goto search
(current page)
/
Focus search box
WeakMap::getIterator »
« WeakMap
PHP 手册
语言参考
预定义接口和类
WeakMap
Change language:
English
Brazilian Portuguese
Chinese (Simplified)
French
German
Japanese
Russian
Spanish
Turkish
Other
Submit a Pull Request
Report a Bug
WeakMap::count
(PHP 8)
WeakMap::count
—
统计 map 中存活实体的数量
说明
public
WeakMap::count
():
int
统计 map 中存活实体的数量。
参数
此函数没有参数。
返回值
返回 map 中存活实体的数量。
+
add a note
User Contributed Notes
There are no user contributed notes for this page.