variant_add

(PHP 5)

variant_add — "Adds" two variant values together and returns the result

Description

mixed variant_add ( mixed $left , mixed $right )

Adds left to right using the following rules (taken from the MSDN library), which correspond to those of Visual Basic:

**Variant Addition Rules**
If	Then
Both expressions are of the string type	Concatenation
One expression is a string type and the other a character	Addition
One expression is numeric and the other is a string	Addition
Both expressions are numeric	Addition
Either expression is NULL	NULL is returned
Both expressions are empty	Integer subtype is returned

See also variant_sub().

Note: 对于所有的变量算法函数，此函数的参数可以要么是 PHP 自身的类型（整型，字符串，浮点型，布尔型或者 NULL），要么是一个 COM，VARIANT 或 DOTNET 类的实例。PHP 自身类型将被转换为变量，使用与 VARIANT 类的构造函数中相同的规则。COM 和 DOTNET 对象将具有其默认属性的值，取得并作为变量值使用。
变量算法函数是 COM 库中与其名称接近的函数的封装。此类函数的更多信息请参考 MSDN 库。PHP 函数命名有少许不同，例如 PHP 中的 variant_add() 对应于 MSDN 文档中的 VarAdd()。

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variant_and

variant_abs

Last updated: Mon, 26 Nov 2007