Ruby on Rails-错误的参数数量

Question

def delete_homework
   Homework.all(:conditions => {:teacher => params.require(:teacher) })

   redirect_to :back
end

This is my controller

<div class="row">
  <div class="col s12">
    <div class="card blue-grey lighten-2">
      <div class="card-content white-text">
        <span class="card-title">Delete Homework</span>
        <form action="/welcome/delete_homework">
          <input type="text" name="teacher" placeholder="Teacher Name">
          <input class="btn waves-effect waves-light" type="submit">
        </form>
      </div>
    </div>
  </div>
</div>

This is the HTML side.

When I try this, ruby gives ArgumentError in WelcomeController#delete_homework wrong number of arguments (given 1, expected 0)

what's wrong? please help. Thank you in advance

Answer 1

Change this line:

Homework.all( your_conditions )

to:

Homework.where( your_conditions )

The all method can't take any parameters. It should only be used when you simply want to grab all the records of a given model from the database.

Answer 2

尝试这个

Homework.where(:teacher => params[:teacher])