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International PHP Conference Berlin 2025
Getting Started
Introduction
A simple tutorial
Language Reference
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Types
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Predefined Variables
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Introduction
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简介 »
« ReflectionException
PHP 手册
函数参考
变量与类型相关扩展
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变量处理
简介
安装/配置
运行时配置
变量处理函数
boolval
— 获取变量的布尔值
debug_zval_dump
— 将表示内部 zval 结构的字符串转储到输出
doubleval
— 别名 floatval
empty
— 检查变量是否为空
floatval
— 获取变量的浮点值
get_debug_type
— 以适合调试的方式获取变量的类型名称
get_defined_vars
— 返回由所有已定义变量所组成的数组
get_resource_id
— 返回给定资源的整数标识符
get_resource_type
— 返回资源类型
gettype
— 获取变量的类型
intval
— 获取变量的整数值
is_array
— 检测变量是否是数组
is_bool
— 检测变量是否是布尔值
is_callable
— 验证值是否可以在当前范围内作为函数调用。
is_countable
— 验证变量内容是否为可数值
is_double
— 别名 is_float
is_float
— 检测变量是否是浮点型
is_int
— 检测变量是否是整数
is_integer
— 别名 is_int
is_iterable
— 验证变量的内容是否为可迭代值
is_long
— 别名 is_int
is_null
— 检测变量是否是 null
is_numeric
— 检测变量是否是数字或数字字符串
is_object
— 检测变量是否是对象
is_real
— 别名 is_float
is_resource
— 查找变量是否为资源
is_scalar
— 查找变量是否是标量
is_string
— 检测变量的类型是否是字符串
isset
— 检测变量是否已声明并且其值不为 null
print_r
— 打印人类可读的变量信息
serialize
— 生成值的可存储表示
settype
— 设置变量的类型
strval
— 获取变量的字符串值
unserialize
— 从已存储的表示中创建 PHP 的值
unset
— 清除指定变量
var_dump
— 打印变量的相关信息
var_export
— 输出或返回变量的可解析字符串表示
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