我有一个哈希数组需要编写通用的检查器,因此我想传入要检查的键的名称。该哈希是使用符号(冒号前缀)作为键定义的。我无法弄清如何正确地使用变量作为键。尽管键存在于哈希中,但使用变量访问它会导致nil。
在IRB中,我这样做:
>> family = { 'husband' => "Homer", 'wife' => "Marge" }
=> {"husband"=>"Homer", "wife"=>"Marge"}
>> somevar = "husband"
=> "husband"
>> family[somevar]
=> "Homer"
>> another_family = { :husband => "Fred", :wife => "Wilma" }
=> {:husband=>"Fred", :wife=>"Wilma"}
>> another_family[somevar]
=> nil
>>
我如何通过变量访问哈希键?或者说,我如何将变量强制转换为符号?