rails4 ajax实现验证用户存在否

假设用户表名是 users ，用户名 字段 是 name

1、需为users对应的建一个controller，同时定义方法checkname

app\controllers\users_controller.rb

class UsersController < ApplicationController
def checkname
if User.where(name: params[:name]).count == 0
render :nothing => true,:status => 200
else
render :nothing => true,:status => 409
end
return
end
end

2、同时要为checkname方法设置路由 ，修改routes.rb,添加

resources :users do
collection do
get 'checkname'
end
end

3、app\views\register\index.html.erb中写这么一句

<%= f.text_field :name,required: true,class:"txt1_bg","data-validate"=> '/users/checkname' %><div id="divName_info"></div>

4、app\assets\javascripts\register.js.coffee

$ ->
$("[data-validate]").blur ->
$this = $(this)
$.get($this.data("validate"),
name: $this.val()
).success(->
$("#divName_info").empty()
$("#divName_info").append ""+"can"
return
).error ->
$("#divName_info").empty()
$("#divName_info").append ""+"exist"
return
return
return

5、调试

讨论