var manager = person.GetDepartment().GetManager();

var manager = person.GetManager();

ASP.NET 2.0 introduced a concept of application offline. This mean that when there is App_Offline.htm file in the root of a web application directory then ASP.NET will shut-down the application, unload the application domain from the server, and stop processing any new incoming requests for that application. In ASP.NET 5, there is an open-issue for supporting this feature. 

namespace Test
{
    internal class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
    }
}

using System.Text.Json.Serialization;

namespace Test
{
    [JsonSerializable(typeof(Person))]
    internal partial class MyJsonContext : JsonSerializerContext
    {
    }
}

Person person = new() { FirstName = "Jane", LastName = "Doe" };
byte[] utf8Json = JsonSerializer.SerializeToUtf8Bytes(person, MyJsonContext.Default.Person);
person = JsonSerializer.Deserialize(utf8Json, MyJsonContext.Default.Person);

namespace System.Text.Json
{
    public static class JsonSerializer
    {
        public static object? Deserialize(ReadOnlySpan<byte> utf8Json, Type returnType, JsonSerializerContext context) => ...;
        public static object? Deserialize(ReadOnlySpan<char> json, Type returnType, JsonSerializerContext context) => ...;
        public static object? Deserialize(string json, Type returnType, JsonSerializerContext context) => ...;
        public static object? Deserialize(ref Utf8JsonReader reader, Type returnType, JsonSerializerContext context) => ...;
        public static ValueTask<object?> DeserializeAsync(Stream utf8Json, Type returnType, JsonSerializerContext context, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static ValueTask<TValue?> DeserializeAsync<TValue>(Stream utf8Json, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static TValue? Deserialize<TValue>(ReadOnlySpan<byte> utf8Json, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
        public static TValue? Deserialize<TValue>(string json, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
        public static TValue? Deserialize<TValue>(ReadOnlySpan<char> json, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
        public static TValue? Deserialize<TValue>(ref Utf8JsonReader reader, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
        public static string Serialize(object? value, Type inputType, JsonSerializerContext context) => ...;
        public static void Serialize(Utf8JsonWriter writer, object? value, Type inputType, JsonSerializerContext context) { }
        public static Task SerializeAsync(Stream utf8Json, object? value, Type inputType, JsonSerializerContext context, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task SerializeAsync<TValue>(Stream utf8Json, TValue value, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static byte[] SerializeToUtf8Bytes(object? value, Type inputType, JsonSerializerContext context) => ...;
        public static byte[] SerializeToUtf8Bytes<TValue>(TValue value, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
        public static void Serialize<TValue>(Utf8JsonWriter writer, TValue value, JsonTypeInfo<TValue> jsonTypeInfo) { }
        public static string Serialize<TValue>(TValue value, JsonTypeInfo<TValue> jsonTypeInfo) => ...;
    }
}

using System.Text.Json.Serialization;

namespace Test
{
    [JsonSourceGenerationOptions(PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase)]
    [JsonSerializable(typeof(Person))]
    internal partial class MyJsonContext : JsonSerializerContext
    {
    }
}

string json = JsonSerializer.Serialize(person, MyJsonContext.Default.Person);
Person person = JsonSerializer.Deserialize(json, MyJsonContext.Default.Person);

services.AddControllers().AddJsonOptions(options => options.AddContext<MyJsonContext>());

[JsonSerializable(typeof(WeatherForecast[]))]
internal partial class MyJsonContext : JsonSerializerContext { }

@code {
    private WeatherForecast[] forecasts;

    private static JsonSerializerOptions Options = new(JsonSerializerDefaults.Web);
    private static MyJsonContext Context = new MyJsonContext(Options);

    protected override async Task OnInitializedAsync()
    {
        forecasts = await Http.GetFromJsonAsync("sample-data/weather.json", Context.WeatherForecastArray);
    }
}

namespace System.Net.Http.Json
{
    public static partial class HttpClientJsonExtensions
    {
        public static Task<object?> GetFromJsonAsync(this HttpClient client, string? requestUri, Type type, JsonSerializerContext context, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<object?> GetFromJsonAsync(this HttpClient client, System.Uri? requestUri, Type type, JsonSerializerContext context, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<TValue?> GetFromJsonAsync<TValue>(this HttpClient client, string? requestUri, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<TValue?> GetFromJsonAsync<TValue>(this HttpClient client, System.Uri? requestUri, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, string? requestUri, TValue value, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, System.Uri? requestUri, TValue value, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, string? requestUri, TValue value, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, System.Uri? requestUri, TValue value, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
    }
    public static partial class HttpContentJsonExtensions
    {
        public static Task<object?> ReadFromJsonAsync(this HttpContent content, Type type, JsonSerializerContext context, CancellationToken cancellationToken = default(CancellationToken)) => ...;
        public static Task<T?> ReadFromJsonAsync<T>(this HttpContent content, JsonTypeInfo<TValue> jsonTypeInfo, CancellationToken cancellationToken = default(CancellationToken)) => ...;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    android:minWidth="25px"
    android:minHeight="25px"
    android:background="#fff">
<include  layout="@layout/toolbarlayout" />
<ListView
android:minWidth="25px"
android:minHeight="25px"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/lvPaziresh" />
</LinearLayout>

namespace sample_22_backend.Models
{
    public class Post
    {
        public int Id { set; get; }
        public string Title { set; get; }
        public string Body { set; get; }

        public int UserId { set; get; }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using sample_22_backend.Models;

namespace sample_22_backend.Services
{
    public interface IPostsDataSource
    {
        List<Post> GetAllPosts();
        bool DeletePost(int id);
        Post AddPost(Post post);
        bool UpdatePost(int id, Post post);
        Post GetPost(int id);
    }

    /// <summary>
    /// هدف صرفا تهیه یک منبع داده آزمایشی ساده تشکیل شده در حافظه است
    /// </summary>
    public class PostsDataSource : IPostsDataSource
    {
        private readonly List<Post> _allPosts;

        public PostsDataSource()
        {
            _allPosts = createDataSource();
        }

        public List<Post> GetAllPosts()
        {
            return _allPosts;
        }

        public Post GetPost(int id)
        {
            return _allPosts.Find(x => x.Id == id);
        }

        public bool DeletePost(int id)
        {
            var item = _allPosts.Find(x => x.Id == id);
            if (item == null)
            {
                return false;
            }

            _allPosts.Remove(item);
            return true;
        }

        public Post AddPost(Post post)
        {
            var id = 1;
            var lastItem = _allPosts.LastOrDefault();
            if (lastItem != null)
            {
                id = lastItem.Id + 1;
            }

            post.Id = id;
            _allPosts.Add(post);
            return post;
        }

        public bool UpdatePost(int id, Post post)
        {
            var item = _allPosts
                .Select((pst, index) => new { Item = pst, Index = index })
                .FirstOrDefault(x => x.Item.Id == id);
            if (item == null || id != post.Id)
            {
                return false;
            }

            _allPosts[item.Index] = post;
            return true;
        }

        private static List<Post> createDataSource()
        {
            var list = new List<Post>();
            var rnd = new Random();
            for (var i = 1; i < 10; i++)
            {
                list.Add(new Post { Id = i, UserId = rnd.Next(1, 1000), Title = $"Title {i} ...", Body = $"Body {i} ..." });
            }
            return list;
        }
    }
}

using System.Collections.Generic;
using Microsoft.AspNetCore.Mvc;
using sample_22_backend.Models;
using sample_22_backend.Services;

namespace sample_22_backend.Controllers
{
    [ApiController]
    [Route("api/[controller]")]
    public class PostsController : ControllerBase
    {
        private readonly IPostsDataSource _postsDataSource;

        public PostsController(IPostsDataSource postsDataSource)
        {
            _postsDataSource = postsDataSource;
        }

        [HttpGet]
        public ActionResult<List<Post>> GetPosts()
        {
            return _postsDataSource.GetAllPosts();
        }

        [HttpGet("{id}")]
        public ActionResult<Post> GetPost(int id)
        {
            var post = _postsDataSource.GetPost(id);
            if (post == null)
            {
                return NotFound();
            }
            return Ok(post);
        }

        [HttpDelete("{id}")]
        public ActionResult DeletePost(int id)
        {
            var deleted = _postsDataSource.DeletePost(id);
            if (deleted)
            {
                return Ok();
            }
            return NotFound();
        }

        [HttpPost]
        public ActionResult<Post> CreatePost([FromBody]Post post)
        {
            post = _postsDataSource.AddPost(post);
            return CreatedAtRoute(nameof(GetPost), new { post.Id }, post);
        }

        [HttpPut("{id}")]
        public ActionResult<Post> UpdatePost(int id, [FromBody]Post post)
        {
            var updated = _postsDataSource.UpdatePost(id, post);
            if (updated)
            {
                return Ok(post);
            }
            return NotFound();
        }
    }
}

> create-react-app sample-22-frontend
> cd sample-22-frontend
> npm start

> npm install --save bootstrap

import "bootstrap/dist/css/bootstrap.css";

import "./App.css";

import React, { Component } from "react";

class App extends Component {
  state = {
    posts: []
  };

  handleAdd = () => {
    console.log("Add");
  };

  handleUpdate = post => {
    console.log("Update", post);
  };

  handleDelete = post => {
    console.log("Delete", post);
  };

  render() {
    return (
      <React.Fragment>
        <button className="btn btn-primary mt-1 mb-1" onClick={this.handleAdd}>
          Add
        </button>
        <table className="table">
          <thead>
            <tr>
              <th>Title</th>
              <th>Update</th>
              <th>Delete</th>
            </tr>
          </thead>
          <tbody>
            {this.state.posts.map(post => (
              <tr key={post.id}>
                <td>{post.title}</td>
                <td>
                  <button
                    className="btn btn-info btn-sm"
                    onClick={() => this.handleUpdate(post)}
                  >
                    Update
                  </button>
                </td>
                <td>
                  <button
                    className="btn btn-danger btn-sm"
                    onClick={() => this.handleDelete(post)}
                  >
                    Delete
                  </button>
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      </React.Fragment>
    );
  }
}

export default App;

> npm install --save axios

Select
[Customer].members on columns
From [Adventure Works]
GO
Select
[Scenario].members on columns
From [Adventure Works]

دو کوئری زیر را در نظر بگیرید :

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].members on rows
From [Adventure Works]

و

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Country].members on rows
From [Adventure Works]

تفاوت این دو کوئری در واکشی اطلاعات از اعضای سطح ساختار سلسله مراتبی دایمنشن می‌باشد. برای توضیح بیشتر ابتدا به خروجی آن‌ها نگاهی بیندازید.

در کوئری اول تمامی سطوح موجود در ساختار سلسله مراتبی دایمنشن مورد نظر واکشی می‌شود. در کوئری دوم فقط سطح کشور از ساختار سلسله مراتبی واکشی می‌شود.

ساختار سلسله مراتبی دایمنشن [ Customer ] در شکل زیر نمایش داده شده است.

امکان واکشی عضوهای یک عضو از ساختار سلسله مراتبی وجود ندارد

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Country].[France].members on rows
From [Adventure Works]

دقت کنید که France خودش عضو سطح Country در ساختار سلسله مراتبی Customer Geography در دایمنشن Customer می‌باشد و دیگر امکان واکشی اعضای این عضو وجود ندارد

بچه‌های یک عضو را به شکل زیر می‌توان واکشی نمود.

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Country].[France].children on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Country].[France].children.children on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
descendants(
[Customer].[Customer Geography].[Country].[France],
[Customer].[Customer Geography].[City]
) on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
descendants(
[Customer].[Customer Geography].[Country].[France],
[Customer].[Customer Geography].[Customer]
) on rows
From [Adventure Works]

Select
[Customer].[Customer Geography].[Customer].[Crystal Zhen] on columns
From [Adventure Works]

Select
exists(
[Customer].[Customer Geography].[Customer].[Crystal Zheng],
[Customer].[Customer Geography].members
  )on columns
From [Adventure Works]

Select
[Measures].[Reseller Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].members on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].[Crystal Zheng].children on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].[Crystal Zheng].parent on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].[Crystal Zheng].parent.parent on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].[Crystal Zheng].parent.parent.parent.parent
on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
[Customer].[Customer Geography].[Customer].[Crystal Zheng].parent
.parent.parent.parent.parent.parent
on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
ancestor(
[Customer].[Customer Geography].[Customer].[Crystal Zheng],
[Customer].[Customer Geography].[City]
)on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
ancestor(
[Customer].[Customer Geography].[Customer].[Crystal Zheng],
[Customer].[Customer Geography].[City]
)on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
ancestor(
[Customer].[Customer Geography].[Customer].[Crystal Zheng],
2
) on rows
From [Adventure Works]

Select
[Measures].[Internet Sales Amount] on columns,
ascendants(
[Customer].[Customer Geography].[Customer].[Crystal Zheng]
  ) on rows
From [Adventure Works]

select
[Measures].[Internet Sales Amount] on columns,
hierarchize(
ascendants(
[Customer].[Customer Geography].[Customer].[Crystal Zheng]
)
) on rows
From [Adventure Works]

برای مرتب سازی یک ساختار سلسله مراتبی از تابع hierarchize() استفاده می‌کنیم. دقت داشته باشید که کار برروی ساختار‌های سلسله مراتبی یکی از قسمت‌های اصلی در MDX Query ‌ها می‌باشد.

ادامه‌ی این مطالب و کار با ساختار‌های سلسله مراتبی را در مقالات بعدی دنبال خواهیم کرد.

void main() {
  // Your app starts here.
}

...
<div>
  <div>
    <input type="text" id="inputName" maxlength="15">
  </div>
</div>
...

import 'dart:html';

void main() {
  querySelector('#inputName').onInput.listen(updateBadge);
}

...

void updateBadge(Event e) { 
  querySelector('#badgeName').text = e.target.value;
}

...

void updateBadge(Event e) { 
  querySelector('#badgeName').text = (e.target as InputElement).value;
}

System.InvalidOperationExceptionWhen called from 'VisitMemberInit', rewriting a node of type 'System.Linq.Expressions.NewExpression' must return a non-null value of the same type. Alternatively, override 'VisitMemberInit' and change it to not visit children of this type. 

protected override Expression VisitMemberInit(MemberInitExpression node)
 {
       if (node.NewExpression.NodeType == ExpressionType.New) 
            return node;
        return base.VisitMemberInit(node);
 }

npm install sql.js --save

const{app,BrowserWindow}=require("electron");

let win;
function onLoad()
{
  win=new BrowserWindow({
    width:800,
    height:600
  });
  win.loadURL(`file://${__dirname}/index.html`);
}

app.on("ready",onLoad());

var path=require("path");
path.exists('filepath",(status)=>
{
....
});
var status=path.existsSync("file");
//===============================
var fs=require("fs");
fs.exists('filepath",(status)=>
{
....
});
var status=path.existsSync("file");

fs.stat('foo.txt', function(err, stat) {
    if(err == null) {
        console.log('فایل موجوده');
    } else if(err.code == 'ENOENT') {
        // فایل وجود نداره
        fs.writeFile('log.txt', 'Some log\n');
    } else {
        //خطای دیگری رخ داده است
    }
});

try {
  stats = fs.statSync(path);
  console.log("File exists.");
}
catch (e) {
  console.log("File does not exist.");
}

const fs = require('fs');
const sql = require('sql.js');

  dbPath = './mydb.sqlite';
  dbExists=false;

try {
  dbExists = fs.statSync(dbPath);
}
catch (e) {
}

if(!dbExists)
{
  //create Database
var sqlStr=fs.readFileSync("./sql.txt");
var db = new sql.Database();
db.run(String(sqlStr));

//write to disk
var data=db.export();
var buffer=new Buffer(data);
fs.writeFileSync(dbPath,buffer);
}
else{
  var buffer = fs.readFileSync(dbPath);
  var db = new sql.Database(buffer);
}

CREATE TABLE numbers (
    id     INT          PRIMARY KEY
                        UNIQUE
                        NOT NULL,
    fname  VARCHAR (20) NOT NULL,
    lname  VARCHAR (30) NOT NULL,
    number VARCHAR (15) NOT NULL
);
insert into numbers values(1,'ali','yeganeh','03111223344');
insert into numbers values(2,'xxx','yyy','45454555');

global.db=db;

app.on('window-all-closed', () => {
  db.close();
  if (process.platform !== 'darwin') {
    app.quit();
  }
});