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AngularJS $scope

A scope connects expression evaluation, watchers and a view lifetime. Scope inheritance can make a field readable from a parent while assignment creates a different child property.

How it works

This maintenance example uses an explicitly annotated $scope injection so older controller code is recognizable. It stores a record under an object property rather than scattering primitives across the scope. A child editing record.note normally changes that shared object property, whereas assigning a new primitive can shadow a parent field. Isolate scopes and component bindings offer more deliberate boundaries for reusable views.

Run the code

AngularJS 1.8.3 is a legacy framework whose official support ended in January 2022. These examples teach maintenance, not a recommendation for a new application. They need a separate local browser page; Bhylu has no AngularJS playground.

In an empty folder save the HTML below as scope.html and the server as lab-server.mjs. Make a vendor folder and save the four pinned libraries there, retaining their MIT notices. With Node 22 or later run node lab-server.mjs scope.html, then open http://127.0.0.1:8136/. Stop that lab before running a different lesson. The server supplies fixed read-only HTTP fixtures; no data is saved and it does not connect to SQL. No PHP, Apache or MySQL configuration changes are needed.

Example

scope.html

<!doctype html>
<html lang="en" ng-app="repairLab" ng-strict-di>
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width,initial-scale=1" />
    <title>AngularJS $scope</title>
    <style>
      :root {
        font:
          18px/1.55 system-ui,
          sans-serif;
        color: #0f3464;
        background: #fff;
        color-scheme: light;
      }
      * {
        box-sizing: border-box;
      }
      body {
        margin: 0;
      }
      main {
        max-width: 50rem;
        margin: auto;
        padding: 1.2rem;
      }
      h1 {
        font-size: 1.65rem;
      }
      label {
        display: block;
        margin: 0.6rem 0;
      }
      input,
      select,
      textarea,
      button {
        font: inherit;
        max-width: 100%;
        padding: 0.35rem;
        margin: 0.2rem;
      }
      button {
        border: 1px solid #034fa0;
        border-radius: 0.25rem;
        background: #034fa0;
        color: white;
      }
      button:disabled {
        opacity: 0.55;
      }
      output,
      [role="status"] {
        display: block;
        min-height: 1.5rem;
      }
      table {
        border-collapse: collapse;
        width: 100%;
      }
      td,
      th {
        padding: 0.4rem;
        border: 1px solid #a5bbd4;
        text-align: left;
      }
      pre {
        white-space: pre-wrap;
        overflow-wrap: anywhere;
      }
      :focus-visible {
        outline: 3px solid #0078d4;
        outline-offset: 3px;
      }
      [ng-cloak] {
        display: none !important;
      }
      .marked {
        font-weight: 700;
      }
      .error {
        color: #a02424;
      }
      :root[data-theme="dark"] {
        color: #d6e7fb;
        background: #061d30;
        color-scheme: dark;
      }
      :root[data-theme="dark"] .error {
        color: #ffb4b4;
      }
    </style>
  </head>
  <body>
    <main ng-controller="DeskController as vm" ng-cloak>
      <h1>Community repair desk</h1>
      <p>AngularJS 1.8.3 · Legacy maintenance lab · Local demonstration</p>
      <p data-result>{{ record.note }}</p>
    </main>
    <script src="/vendor/angular.min.js"></script>
    <script>
      (function () {
        "use strict";
        var app = angular.module("repairLab", []);
        app.controller("DeskController", [
          "$scope",
          function ($scope) {
            $scope.record = { note: "Inspect before return" };
          },
        ]);
      })();
    </script>
  </body>
</html>
Focus on the bindings and controller

This excerpt leaves out the document shell, styles and library files. Use the complete download to run it.


<p data-result>{{ record.note }}</p>
<script>
  (function () {
    "use strict";
    var app = angular.module("repairLab", []);
    app.controller("DeskController", [
      "$scope",
      function ($scope) {
        $scope.record = { note: "Inspect before return" };
      },
    ]);
  })();
</script>

Expected result

Inspect before return

The template reads record from the controller’s scope. Its separate vm alias remains available for controllerAs examples elsewhere, but this page deliberately demonstrates the older scope surface. A scope destroyed with its view should no longer own active listeners or timers; later lessons test that cleanup.

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