Description
int 
variant_cmp ( mixed left, mixed right [, int lcid [, int flags]] )
     Compares left with right
     and returns one of the following values:
     
表格 1. Variant Comparision Results
| value | meaning | 
|---|
| VARCMP_LT | left is less than
         right | 
| VARCMP_EQ | left is equal to
         right | 
| VARCMP_GT | left is greater than
         right | 
| VARCMP_NULL | Either left,
         right or both are NULL | 
    This function will only compare scalar values, not arrays or variant records.
   
    lcid is a valid Locale Identifier to use when
    comparing strings (this affects string collation).
    flags can be one or more of the following values
    OR'd together, and affects string comparisons:
     
表格 2. Variant Comparision Flags
| value | meaning | 
|---|
| NORM_IGNORECASE | Compare case insensitively | 
| NORM_IGNORENONSPACE | Ignore nonspacing characters | 
| NORM_IGNORESYMBOLS | Ignore symbols | 
| NORM_IGNOREWIDTH | Ignore string width | 
| NORM_IGNOREKANATYPE | Ignore Kana type | 
| NORM_IGNOREKASHIDA | Ignore Arabic kashida characters | 
注: 
  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()。