CRUD Devise Example

_form.html.erb

<%= form_for(@user) do |f| %>
  <% if @user.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@user.errors.count, "error") %> prohibited this user from being saved:</h2>

      <ul>
      <% @user.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
    
  <p><%= f.label :username %><br />
  <%= f.text_field :username %></p>

  <p><%= f.label :first_name %><br />
  <%= f.text_field :first_name %></p>

  <p><%= f.label :last_name %><br />
  <%= f.text_field :last_name %></p>

  <p><%= f.label :email %><br />
  <%= f.email_field :email %></p>

  <% if action_name == "new" %>
  <p><%= f.label :password, "New password" %><br />
  <%= f.password_field :password %></p>

  <p><%= f.label :password_confirmation %><br />
  <%= f.password_field :password_confirmation %></p>
  <% end %>

  <p>
    <%= f.label :role %><br />
    <%= f.collection_select :role, User::ROLES, :to_s, :humanize %>
  </p>

  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

_passwords.html.erb

<%= form_for(@user) do |f| %>
  <% if @user.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@user.errors.count, "error") %> prohibited this user from being saved:</h2>

      <ul>
      <% @user.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
    
  <p><%= f.label :password, "New password" %><br />
  <%= f.password_field :password %></p>

  <p><%= f.label :password_confirmation %><br />
  <%= f.password_field :password_confirmation %></p>

  <div class="actions">
    <%= f.submit "Change password" %>
  </div>
<% end %>

edit.html.erb

<h2>Edit user</h2>

<%= render 'form' %>
<p></p>
<%= render 'passwords' %>

<%= link_to 'All users', users_path %>

index.html.erb

<h1>All Users</h1>

<table id="users">
	<thead>
		<tr>
			<th>Username</th>
			<th>First Name</th>
			<th>Last Name</th>
			<th>Email</th>
			<th>Login Count</th>
			<th>Last Sign In</th>
			<th>Role</th>
			<th>Created At</th>
			<th>Last Edited</th>
			<th></th>
			<th></th>
		</tr>
	</thead>
	<tbody>
		<% @users.each do |user| %>
		<tr>
			<th><%= user.username %></th>
			<th><%= user.first_name %></th>
			<th><%= user.last_name %></th>
			<th><%= user.email %></th>
			<th><%= user.sign_in_count %></th>
			<th><%if user.last_sign_in_at.blank? %>Never logged in<% else %><%= time_ago_in_words(user.last_sign_in_at.to_datetime)+' ago' %><% end %></th>
			<th><%= user.role %></th>
			<th><%= user.created_at.to_s(:datetime).downcase %></th>
			<th><%= user.updated_at.to_s(:datetime).downcase %></th>
			<th><%= link_to "Edit", edit_user_path(user) %></th>
			<th><%= link_to "Delete", user, :method => :delete, :confirm => "Are you sure?" %></th>
		</tr>
		<% end %>
	</tbody>


</table>

<p><%= link_to "New User", new_user_path %></p>

new.html.erb

<h2>Sign up</h2>

<%= render 'form' %>

<%= link_to 'All users', users_path %>

show.html.erb

<p><%= @user.username %></p>
<p><%= @user.first_name %></p>
<p><%= @user.last_name %></p>
<p><%= @user.email %></p>

users_controller.html.erb

class UsersController < ApplicationController
  # GET /users
  # GET /users.json
  def index
    @users = User.all

    respond_to do |format|
      format.html # index.html.erb
      format.json { render :json => @users }
    end
  end


  # GET /users/1
  # GET /users/1.json
  def show
    @user = User.find(params[:id])

    respond_to do |format|
      format.html # show.html.erb
      format.json { render :json => @user }
    end
  end

  # GET /users/new
  # GET /users/new.json
  def new
    @user = User.new

    respond_to do |format|
      format.html # new.html.erb
      format.json { render :json => @user }
    end
  end

  # GET /users/1/edit
  def edit
    @user = User.find(params[:id])
  end

  # POST /users
  # POST /users.json
  def create
    @user = User.new(params[:user])

    respond_to do |format|
      if @user.save
        format.html { redirect_to @user, :notice => 'User was successfully created.' }
        format.json { render :json => @user, :status => :created, :location => @user }
      else
        format.html { render :action => "new" }
        format.json { render :json => @user.errors, :status => :unprocessable_entity }
      end
    end
  end

  # PUT /users/1
  # PUT /users/1.json
  def update
    @user = User.find(params[:id])

    respond_to do |format|
      if @user.update_attributes(params[:user])
        format.html { redirect_to @user, :notice => 'User was successfully updated.' }
        format.json { head :ok }
      else
        format.html { render :action => "edit" }
        format.json { render :json => @user.errors, :status => :unprocessable_entity }
      end
    end
  end

  # DELETE /users/1
  # DELETE /users/1.json
  def destroy
    @user = User.find(params[:id])
    @user.destroy

    respond_to do |format|
      format.html { redirect_to users_url }
      format.json { head :ok }
    end
  end
end

thank you so much!!!!