How to resolve NoMethodError in ror version 4 - ruby-on-rails

Question

When I clicked on "display your data" link it is showing me the following error.
Error:
NoMethodError in Users#show
Showing C:/Site/new/app/views/users/show.html.erb where line #10 raised:
undefined method `email' for #<User::ActiveRecord_Relation:0x2bd81e8>
My code snippets are given below.
views/users/index.html.erb
<h1>Choose your option</h1>
<%= link_to "Enter your data",users_new_path %>
<%= link_to "Display your data",users_show_path %>
views/users/new.html.erb
<h1>Enter your data here</h1>
<%= form_for #user,:url => {:action => 'create'} do |f| %>
<% if #user.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#user.errors.count, "error") %> prohibited this post from being saved:</h2>
<ul>
<% #user.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<%= f.text_field:name,placeholder:"Enter your name" %><br>
<%= f.email_field:email,placeholder:"Enter your email" %><br>
<%= f.text_field:message,placeholder:"Enter your message"%><br>
<%= f.submit "Submit" %>
<% end %>
views/users/show.html.erb
<h1>Display your data</h1>
<ul>
<li>
<p>
<strong>Name:</strong>
<%= #user.name %>
</p>
<p>
<strong>Email:</strong>
<%= #user.email %>
</p>
<p>
<strong>Message:</strong>
<%= #user.message %>
</p>
</li>
</ul>
<%= link_to "Edit",users_edit_path(:id => t.id) %><%= link_to "Delete",users_delete_path(:id => t.id),data: { confirm: 'Are you sure to delete it ?' } %>
<%= link_to "Back",users_index_path %>
controller/users_controller.rb
class UsersController < ApplicationController
def index
end
def new
#user=User.new
end
def create
#user=User.new(users_params)
if #user.save
flash[:notice]="Your data is saved succesfully"
flash[:color]="valid"
redirect_to :action => 'index'
else
flash[:alert]="You are entering wrong data"
flash[:color]="invalid"
render :new
end
end
def show
#user=User.all
end
def delete
#user=User.find(params[:id])
#user.delete
end
def edit
#edit=User.find(params[:id])
#user=User.new
end
def update
#user=User.find(params[:id])
if #user.update_attributes(update_params)
flash[:notice]="Your data has updated successfully"
flash[:color]="valid"
redirect_to :action => 'index'
else
flash[:alert]="Your data could not update..check it.."
flash[:color]="invalid"
render :edit
end
end
private
def users_params
params.require(:user).permit(:name, :email, :message,pets_attributes: [:name, :email,:message])
end
def update_params
params.require (:user).permit(:name,:email,:message,pets_attributes: [:name,:email,:message])
end
end
model/user.rb
class User < ActiveRecord::Base
has_many :pets
accepts_nested_attributes_for :pets
EMAIL_REGEX = /\A[A-Z0-9._%+-]+#[A-Z0-9.-]+\.[A-Z]{2,4}\z/i
validates :name, :presence => true,:length => { :minimum => 5 }
validates :email, :presence => true, :uniqueness => true, :format => EMAIL_REGEX
validates :message, :presence => true
end

Answer 1

You should fix your show action from:
def show
#user = User.all
end
to:
def show
#user = User.find(params[:id])
end

Answer 2

In show action, you have
#user = User.all
which assigns relation with all users to #user variable. That's why you have this error, because you can't query whole relation for email. You should have:
#user = User.find(params[:id])
User.find(params[:id]) returns single User instance.

Answer 3

def show
#user=User.all
end
This will return array of users instead of user, so in order to call email on it you have to iterate loop over it.
<% user in #users %> <!-- I have change #user to #users in show method -->
<h1>Display your data</h1>
<ul>
<li>
<p>
<strong>Name:</strong>
<%= user.name %>
</p>
<p>
<strong>Email:</strong>
<%= user.email %>
</p>
<p>
<strong>Message:</strong>
<%= user.message %>
</p>
</li>
</ul>
<%= link_to "Edit",users_edit_path(:id => t.id) %><%= link_to "Delete",users_delete_path(:id => t.id),data: { confirm: 'Are you sure to delete it ?' } %>
<%= link_to "Back",users_index_path %>
<% end %>
Or just change show method
#user = User.find(params[:id])

Answer 4

fix your show action.
replace
#user = User.all
with
#user = User.find(params[:id])