public class EfRolesService : IRolesService
    {
        readonly IUnitOfWork _uow;
        readonly IDbSet<Role> _roles;
        public EfRolesService(IUnitOfWork uow)
        {
            _uow = uow;
            _roles = _uow.Set<Role>();
        }

        public IList<Role> FindUserRoles(int userId)
        {
            var query = from role in _roles
                        from user in role.Users
                        where user.Id == userId
                        select role;

            return query.OrderBy(x => x.Name).ToList();
        }

        public string[] GetRolesForUser(int userId)
        {
            var roles = FindUserRoles(userId);
            if (roles == null || !roles.Any())
            {
                return new string[] { };
            }

            return roles.Select(x => x.Name).ToArray();
        }

        public bool IsUserInRole(int userId, string roleName)
        {
            var query = from role in _roles
                        where role.Name == roleName
                        from user in role.Users
                        where user.Id == userId
                        select role;
            var userRole = query.FirstOrDefault();
            return userRole != null;
        }
    }

    public class CustomRoleProvider : RoleProvider
    {
        public override bool IsUserInRole(string username, string roleName)
        {
            // Since the role provider, in this case the CustomRoleProvider is instantiated by 
            // the ASP.NET framework the best solution is to use the service locator pattern. 
            // The service locator pattern is normally considered to be an anti-pattern but 
            // sometimes you have to be pragmatic and accept the limitation on the framework 
            // that is being used (in this case the ASP.NET framework).

            var rolesService = ObjectFactory.GetInstance<IRolesService>();
            return rolesService.IsUserInRole(username.ToInt(), roleName);
        }

        public override string[] GetRolesForUser(string username)
        {
            var rolesService = ObjectFactory.GetInstance<IRolesService>();
            return rolesService.GetRolesForUser(username.ToInt());
        }
// مابقی نیازی نیست پیاده سازی شوند

  handleDelete = async post => {
    const posts = this.state.posts.filter(item => item.id !== post.id);
    this.setState({ posts });

    await axios.delete(`${apiEndpoint}/${post.id}`);
  };

  handleDelete = async post => {
    const originalPosts = this.state.posts;

    const posts = this.state.posts.filter(item => item.id !== post.id);
    this.setState({ posts }); // Optimistic Update

    try {
      await axios.delete(`${apiEndpoint}/${post.id}`);
    } catch (ex) {
      alert("An error occurred when deleting a post!");
      this.setState({ posts: originalPosts }); // Undo changes
    }
  };

try {
  await axios.delete(`${apiEndpoint}/${post.id}`);
} catch (ex) {
  if (ex.response && ex.response.status === 404) {
     alert("This post has already been deleted!");
  } else {
     console.log("Error", ex);
     alert("An unexpected error occurred when deleting a post!");
  }

  this.setState({ posts: originalPosts }); // Undo changes
}

import "./App.css";

import axios from "axios";
import React, { Component } from "react";

axios.interceptors.response.use(null, error => {
  console.log("interceptor called.");
  return Promise.reject(error);
});

const apiEndpoint = "https://localhost:5001/api/posts";
class App extends Component {

axios.interceptors.response.use(null, error => {
  const expectedError =
    error.response &&
    error.response.status >= 400 &&
    error.response.status < 500;

  if (!expectedError) {
    console.log("Error", error);
    alert("An unexpected error occurred when deleting a post!");
  }

  return Promise.reject(error);
});

import axios from "axios";

axios.interceptors.response.use(null, error => {
  const expectedError =
    error.response &&
    error.response.status >= 400 &&
    error.response.status < 500;

  if (!expectedError) {
    console.log("Error", error);
    alert("An unexpected error occurred when deleting a post!");
  }

  return Promise.reject(error);
});

export default {
  get: axios.get,
  post: axios.post,
  put: axios.put,
  delete: axios.delete
};

import http from "./services/httpService";

{
   "apiEndpoint" : "https://localhost:5001/api/posts"
}

import config from "./config.json";

> npm i react-toastify --save

import { ToastContainer } from "react-toastify";
import "react-toastify/dist/ReactToastify.css";

  render() {
    return (
      <React.Fragment>
        <ToastContainer />

import { toast } from "react-toastify";
// ...

axios.interceptors.response.use(null, error => {
  // ...
  if (!expectedError) {
    // ...
    toast.error("An unexpected error occurrred.");
  }

{
_id: ObjectID(‘4bf9e8e17cef4644108761bb’),
Title: ‘NoSQL Part3’,
url: ‘https://www.dntips.ir/yyy/xxxx’,
author: ‘hamid samani’,
tags: [‘databases’,’mongoDB’],
comments:[
{user: ‘unknown user’,
 text:’unknown test’
},
{user:unknown user2’,
 text:’unknown text2
}
]
}

CREATE TABLE posts (
    id INT NOT NULL
        AUTO_INCREMENT,
    author_id INT NOT NULL,
    url VARCHAR(50),
    PRIMARY KEY (id)
)

db.posts.insert({id: “256” , author_id:”546”,url:"http://example.com/xxx"}) // با قرار دادن مقدار نوع ساختار مشخص می‌شود 

SELECT * from posts
WHERE author_id > 100

db.posts.find({author_id:{$gt:”1000”}})

UPDATE posts
SET author_id= "123"

db.posts.update({ $set: { author_id: "123" }})

DELETE FROM posts
WHERE author_id= "654"

db.posts.remove( { author_id: "654" } )

<h2>About Ember Blog</h2>

<p>Bla bla bla!</p>

<button class="btn btn-primary" {{action 'showRealName' }}>more info</button>

Blogger.AboutController = Ember.Controller.extend({
  actions: {
   showRealName: function () {
    alert("You clicked at showRealName of AboutController.");
   }
  }
});

 <script src="Scripts/Controllers/about.js" type="text/javascript"></script>

<h1>Contact</h1>
<div class="row">
  <div class="col-md-6">
   <p>
    Want to get in touch?
    <ul>
      <li>{{#link-to 'phone'}}Phone{{/link-to}}</li>
      <li>{{#link-to 'email'}}Email{{/link-to}}</li>
    </ul>
   </p>
 
   <p>
    Or, click here to send a secret message:
   </p>
   <button class="btn btn-primary" {{action 'sendMessage' }}>Send message</button>
  </div>
  <div class="col-md-6">
   {{outlet}}
  </div>
</div>

Blogger.ContactController = Ember.Controller.extend({
  actions: {
   sendMessage: function () {
    var message = prompt('Type your message here:');
   }
  }
});

 <script src="Scripts/Controllers/contact.js" type="text/javascript"></script>

<h2>About Ember Blog</h2>
<p>Bla bla bla!</p>
<button class="btn btn-primary" {{action 'showRealName' }}>more info</button>
 
{{#if isAuthorShowing}}
<button class="btn btn-warning" {{action 'hideAuthor' }}>Hide Image</button>
<p><img src="Content/images/ember-productivity-sm.png"></p>
{{else}}
<button class="btn btn-info" {{action 'showAuthor' }}>Show Image</button>
{{/if}}

Blogger.AboutController = Ember.Controller.extend({
  isAuthorShowing: false,
  actions: {
   showRealName: function () {
    alert("You clicked at showRealName of AboutController.");
   },
   showAuthor: function () {
    this.set('isAuthorShowing', true);
   },
   hideAuthor: function () {
    this.set('isAuthorShowing', false);
   }
  }
});

<h1>Contact</h1>
<div class="row">
  <div class="col-md-6">
   <p>
    Want to get in touch?
    <ul>
      <li>{{#link-to 'phone'}}Phone{{/link-to}}</li>
      <li>{{#link-to 'email'}}Email{{/link-to}}</li>
    </ul>
   </p>
   {{#if messageSent}}
   <p>
    Thank you. Your message has been sent.
    Your confirmation number is {{confirmationNumber}}.
   </p>
   {{else}}
   <p>
    Or, click here to send a secret message:
   </p>
   <button class="btn btn-primary" {{action 'sendMessage' }}>Send message</button>
   {{/if}}
  </div>
  <div class="col-md-6">
   {{outlet}}
  </div>
</div>

Blogger.ContactController = Ember.Controller.extend({
  messageSent: false,
  actions: {
   sendMessage: function () {
    var message = prompt('Type your message here:');
    if (message) {
      this.set('confirmationNumber', Math.round(Math.random() * 100000));
      this.set('messageSent', true);
    }
   }
  }
});

function getNewInfo(){
  $.ajax("url", function (newinfo) {
      // do something with the data
  // start the new request
      getNewINfo();
  });
}
// start the polling loop
getNewInfo();

var eventSrc = new EventSource("url");
    // register event handler for the message
    eventSrc.addEventListener( "message",function (evt) {
    //process the data
});

var socket = new WebSocket("url");
socket.onmessage = function (msg) {
var newInfo = msg.data;
// do something with the data
}
// client can also send request to server
socket.send(.... )

 PM> Install-Package Microsoft.AspNet.SignalR.Sample

Button btn = FindViewById<Button>(Resource.Id.button1);

FindViewById<EditText>(Resource.Id.txtname).Text = "";

Intent _intent = new Intent(this, typeof(Activity2));
StartActivity(_intent);

Intent _intent = new Intent(this, typeof(Activity2));
string Test="Vlaueone";

_intent.PutExtra("mainactivity", Test);
StartActivity(_intent);

string Getintent = Intent.GetStringExtra("mainactivity");

List<Product> products;
products = new List<Product>();
Product p = new Product
            {

                name = FindViewById<EditText>(Resource.Id.mainedittextname).Text,
                price = Convert.ToInt32(FindViewById<EditText>(Resource.Id.mainedittextprice).Text)
            };
products.Add(p);
Intent _intent = new Intent(this, typeof(Activity2));
_intent.PutExtra("products", JsonConvert.SerializeObject(products));
StartActivity(_intent);

var p = JsonConvert.DeserializeObject<List<Product>>(Intent.GetStringExtra("products"));
foreach (var item in p)
{
   Toast.MakeText(this, $" {item.name} , {item.price}",
                  ToastLength.Long).Show();
};

//set alert for executing the task
AlertDialog.Builder alert = new AlertDialog.Builder(this);
alert.SetTitle("Confirm delete");
alert.SetMessage("Lorem ipsum dolor sit amet, consectetuer adipiscing elit.");
alert.SetPositiveButton("Delete", (senderAlert, args) =>
            {
                Toast.MakeText(this, "Deleted!", ToastLength.Short).Show();
            });

alert.SetNegativeButton("Cancel", (senderAlert, args) =>
            {
                Toast.MakeText(this, "Cancelled!", ToastLength.Short).Show();
            });

Dialog dialog = alert.Create();
dialog.Show();

public class DialogFragmentActivity : DialogFragment
{
        public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
        {
            var dlg = inflater.Inflate(Resource.Layout.layoutDialog, container, false);
            return dlg;
        }
}

DialogFragmentActivity dlg = new DialogFragmentActivity ();
dlg.Show(this.FragmentManager, "Fragment");

public override void OnStart()
{
            base.OnStart();
            Dialog dialog = Dialog;
            if (dialog != null)
            {
                dialog.Window.SetLayout(ViewGroup.LayoutParams.MatchParent, ViewGroup.LayoutParams.WrapContent);
                dialog.Window.SetBackgroundDrawable(new ColorDrawable(Color.Transparent));
            }
}

public override Dialog OnCreateDialog(Bundle savedInstanceState)
{
            Dialog NotTitle = base.OnCreateDialog(savedInstanceState);
            NotTitle.Window.RequestFeature(WindowFeatures.NoTitle);

            return NotTitle;
}