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#7 Get Authors of Books (sub-items) to show and for sorting

Basic Use of List book.Authors

This example shows the books, and we want to LINQ on the Authors. We must tell the compiler it's a list, so that LINQ can use Select(...).

  1. Hitchhikers Guide to the Galaxy by Douglas Adams
  2. Good Omens by Neil Gaiman, Terry Pratchett
  3. Phishing for Phools by George Akerlof
  4. The Last Continent by Terry Pratchett

<ol>
  @foreach(var book in books) {
    // To work with a list coming off a dynamic object, we have to tell the compiler it's a dynamic list
    var authors = (book.Authors as Dynlist)
      .Select(a => a.FirstName + " " + a.LastName);

    <li><strong>@book.Title</strong>
      by @string.Join(", ", authors.OrderBy(ln => ln)) 
    </li>
  }
</ol>

OrderBy Amount of Authors

This example shows Z-A ordering, where we count the authors to sort.

  1. Good Omens by Neil Gaiman,Terry Pratchett (2 author)
  2. Hitchhikers Guide to the Galaxy by Douglas Adams (1 author)
  3. Phishing for Phools by George Akerlof (1 author)
  4. The Last Continent by Terry Pratchett (1 author)

<ol>
  @foreach(var book in books.OrderByDescending(p => p.Authors.Count)) {
    var authors = (book.Authors as Dynlist).Select(a => a.FirstName + " " + a.LastName);
    <li><strong>@book.Title</strong> 
      by @string.Join(",", authors.OrderBy(ln => ln)) (@book.Authors.Count author) 
    </li>
  }
</ol>
#7 Get Authors of Books (sub-items) to show and for sorting

Source Code of this file

Below you'll see the source code of the file. Note that we're just showing the main part, and hiding some parts of the file which are not relevant for understanding the essentials. Click to expand the code

@inherits Custom.Hybrid.Razor12
@using System.Linq;
@using Dynlist = System.Collections.Generic.IEnumerable<dynamic>;

<!-- unimportant stuff, hidden -->

@{
  var persons = AsList(App.Data["Persons"]);
  var books = AsList(App.Data["Books"]);
}

@Html.Partial("_header.cshtml")

<div class="row">
  <div class="col-lg-7">
    <h2>Accessing Authors, a List inside of Books</h2>
  </div>
  <div class="col-lg-5">
    @Html.Partial("../shared/_InfoSection.cshtml", new { Data = viewMd.Specs.Resources, Title = "Resources" })
  </div>
</div>

<h3>Basic Use of List book.Authors</h3>
<p>This example shows the books, and we want to LINQ on the Authors. We must tell the compiler it's a list, so that LINQ can use <code>Select(...)</code>.</p>

<ol>
  @foreach(var book in books) {
    // To work with a list coming off a dynamic object, we have to tell the compiler it's a dynamic list
    var authors = (book.Authors as Dynlist)
      .Select(a => a.FirstName + " " + a.LastName);

    <li><strong>@book.Title</strong>
      by @string.Join(", ", authors.OrderBy(ln => ln)) 
    </li>
  }
</ol>



<hr>

<h3>OrderBy Amount of Authors</h3>
<p>This example shows Z-A ordering, where we count the authors to sort.</p>

<ol>
  @foreach(var book in books.OrderByDescending(p => p.Authors.Count)) {
    var authors = (book.Authors as Dynlist).Select(a => a.FirstName + " " + a.LastName);
    <li><strong>@book.Title</strong> 
      by @string.Join(",", authors.OrderBy(ln => ln)) (@book.Authors.Count author) 
    </li>
  }
</ol>




<!-- unimportant stuff, hidden -->