如何在 Rails 中提交布尔参数? [英] How do I submit a boolean parameter in Rails?

问题描述

我正在提交一个值为 true 的参数 show_all.此值与模型无关.

I'm submitting a parameter show_all with the value true. This value isn't associated with a model.

我的控制器正在将此参数分配给一个实例变量:

My controller is assigning this parameter to an instance variable:

@show_all = params[:show_all]

但是，@show_all.is_a?String 和 if @show_all == true 总是失败.

However, @show_all.is_a? String, and if @show_all == true always fails.

Rails 将哪些值解析为布尔值?如何明确指定我的参数是布尔值，而不是字符串?

What values does Rails parse as booleans? How can I explicitly specify that my parameter is a boolean, and not a string?

推荐答案

我想对 zetetic 的答案发表评论，但由于我不能这样做，所以我将其作为答案发布.

I wanted to comment on zetetic answer but as I can't do that yet I'll post this as an answer.

如果你使用

@show_all = params[:show_all] == "1"

那么你可以删除 吗?true : false 因为 params[:show_all] == "1" 语句本身将评估为 true 或 false，因此不需要三元运算符.

then you can drop ? true : false because params[:show_all] == "1" statement itself will evaluate to true or false and thus ternary operator is not needed.

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