使用 Ruby 的instance_variable_set 动态变量名
我正在尝试使用 instance_variable_set 创建一组具有不同实例名称的实例来更改实例名称，但我似乎无法将其更改为 工作。
for i in 0..3 do
username_str = String.new
username_str = 'user_' + i.to_s
username_new = User.new
username_new.instance_variable_set("@#{WHAT_DO_I_PUT_HERE?}", username_str)
username_new = User.create(:username => username_str)
end
我不明白的部分是我应该在instance_variable_set的第一个字段中放入什么，其中我有“WHAT_DO_I_PUT_HERE？”？
I'm trying to create a set of instances that have different instance names using instance_variable_set to change the instance name and I can't seem to get it to
work.
for i in 0..3 do
username_str = String.new
username_str = 'user_' + i.to_s
username_new = User.new
username_new.instance_variable_set("@#{WHAT_DO_I_PUT_HERE?}", username_str)
username_new = User.create(:username => username_str)
end
The part I can't figure out is what do I put in the first field of instance_variable_set where I have "WHAT_DO_I_PUT_HERE?"?
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实例变量可能不是适合这项工作的工具。如果您只想创建三个用户，那么：
如果您需要保留 User 对象以供以后使用，那么您可以使用数组：
之后
@users[0]将检索第一个User 的实例，@users[1]第二个，&c。Instance variables might be the wrong tool for the job. If all you want to do is create three users, then:
If you need to retain the User objects for later use, then you can use an array:
after which
@users[0]will retrieve the first instance of User,@users[1]the second, &c.您可以放置一个包含要设置的实例变量名称的字符串。或者，如果您没有这样的字符串，您可以跳过字符串插值并自己在其中写入实例变量的名称。
You would put a string containing the name of the instance variable you want to set. Alternatively, if you do not have such a string, you could just skip the string interpolation and write the name of the instance variable in there yourself.