Ruby on rails “如何替换”；插入空格或删除第一个和最后一个符号？_Ruby On Rails_String_Character

Ruby on rails “如何替换”；插入空格或删除第一个和最后一个符号？

ruby-on-rails string

Ruby on rails “如何替换”；插入空格或删除第一个和最后一个符号？,ruby-on-rails,string,character,Ruby On Rails,String,Character,我获取xml数据，并从中获得价值。我需要删除符号[和] 这是我的代码，它给出了关于未设计变量的错误： @xml = XmlSimple.xml_in(res.content)//here I get xml document payKey = @xml["payKey"]//gere I get needed value //it looks like "[some character]" so I need to delete [ and

我获取xml数据，并从中获得价值。我需要删除符号[和] 这是我的代码，它给出了关于未设计变量的错误：

         @xml = XmlSimple.xml_in(res.content)//here I get xml document
         payKey = @xml["payKey"]//gere I get needed value
         //it looks like "[some character]" so I need to delete [ and ]
         //I tried
         payKey = @xml["payKey"].to_s()//to use tr method
         payKey = payKey.tr("[]", "")//replacing
        redirect_to "https://svcs.sandbox.paypal.com/AdaptivePayments/Pay?cmd=_ap-payment&paykey=#{paykey}"//inserting into url

结果：

            svcs.sandbox.paypal.com/AdaptivePayments/Pay?cmd=_ap-payment&paykey="AP-7NK73769LH704515X"

所以我需要删除“标志。有人能帮我吗？

我愚蠢的回答。”

  payKey = payKey[1..20]