相关疑难解决方法(0)

显然,在PowerShell(第3版)中并非所有$null都是相同的:

    >function emptyArray() { @() }
    >$l_t = @() ; $l_t.Count
0
    >$l_t1 = @(); $l_t1 -eq $null; $l_t1.count; $l_t1.gettype()
0
IsPublic IsSerial Name                                     BaseType                                                         
-------- -------- ----                                     --------                                                         
True     True     Object[]                                 System.Array                                                     
    >$l_t += $l_t1; $l_t.Count
0
    >$l_t += emptyArray; $l_t.Count
0
    >$l_t2 = emptyArray; $l_t2 -eq $null; $l_t2.Count; $l_t2.gettype()
True
0
You cannot call a method on a null-valued expression.
At line:1 char:38
+ $l_t2 = emptyArray; $l_t2 -eq $null; $l_t2.Count; $l_t2.gettype()
+                                      ~~~~~~~~~~~~~~~
  + CategoryInfo …