JS-Const-Variable-with-Array-&-Objects.html

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    <h1>JS Const Variable with Array & Objects</h1>
    <hr />

    <h3>CONST ARRAYS</h3>

    <p>
      The code above has an array variable called numbers holding three values.
      Even though the numbers array is a const you’re able to update or change
      the variable. For example, you can add another number to the numbers array
      by using the push method.&nbsp;Methods are actions you perform on the
      array or object.<br />
      <br />
      const numbers = [1,2,3];<br />
      numbers.push(4);<br />
      console.log(numbers) // Outpusts [1,2,3,4];
    </p>

    <hr />
    <h3>CONST OBJECTS</h3>

    <p>
      The modifying principle applies to an object for example.<br />
      <br />
      const user = {<br />
      &nbsp; name: "Gary",<br />
      }<br />
      <br />
      user.age = 29<br />
      console.log(user) // {name: "Gary", age: 29<br />
      &nbsp;
    </p>

    <p>
      The code above creates a user object with a name property then it assigns
      a new age property to object. One thing to remember const does not stop
      array and objects from being modified it only stops the variable itself
      from being reassigned or being overwritten for example.<br />
      <br />
      const user = {<br />
      &nbsp; name: "Gary",<br />
      }<br />
      <br />
      person = { name: "Bob" } // Uncaught TypeError: Assignment to constant
      variable.<br />
      &nbsp;
    </p>

    <pre
      class="language-markup"
      tabindex="0"
    ><code class="language-markup"><span class="token doctype"><span class="token punctuation">&lt;!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>html</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>head</span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>title</span><span class="token punctuation">&gt;</span></span>JavaScript<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>title</span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>script</span><span class="token punctuation">&gt;</span></span><span class="token script"><span class="token language-javascript">
    <span class="token keyword">const</span> a <span class="token operator">=</span> <span class="token punctuation">{</span>
      <span class="token literal-property property">name</span> <span class="token operator">:</span> <span class="token string">"Ram"</span><span class="token punctuation">,</span>
      <span class="token literal-property property">age</span> <span class="token operator">:</span> <span class="token number">25</span>
    <span class="token punctuation">}</span><span class="token punctuation">;</span>

    a<span class="token punctuation">.</span>name <span class="token operator">=</span> <span class="token string">"Yahoo Baba"</span><span class="token punctuation">;</span>
    a<span class="token punctuation">.</span>age <span class="token operator">=</span> <span class="token number">55</span><span class="token punctuation">;</span>
    console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span>
  </span></span><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>script</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>head</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>body</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>body</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>html</span><span class="token punctuation">&gt;</span></span></code></pre>
    <hr />
  </body>
  <script>
    "use strict";
    const ary = [50, 40, 30];
    ary[1] = 10;
    console.log(ary);

    const obj = { name: "Hamza Khan Lodhi", age: 17 };
    obj.age = 10;
    console.log(obj);
  </script>
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