Difference between revisions of "DOM Creating content"

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==Create img==
==Create img==
<div class='qu'>
<div class='qu'>
You can create a '''img''' element an set the '''src'''.
You can create a '''img''' element and set the '''src'''.
In this example you must set the '''src''' and the '''style''' of the new element '''a'''.
In this example you must set the '''src''' and the '''style''' of the new element '''a'''.
  a.style = 'width:100px;border:solid;';
  a.style = 'width:100px;border:solid;';

Revision as of 06:34, 11 September 2021




Create Content

You can create a div element an set the content.

We use the document method createElement and the DOM node method append

let e = document.createElement('div');
e.innerHTML = 'Hello';
document.body.append(e);
let e = document.createElement('div');
e.innerHTML = 'Hello world';
document.body.append(e);

Create img

You can create a img element and set the src. In this example you must set the src and the style of the new element a.

a.style = 'width:100px;border:solid;';

These are CSS properties.

let a = document.createElement('img');
a.src = '/flags/fr.png';
document.body.append(a);
let a = document.createElement('img');
a.src = '/flags/fr.png';
a.style = 'width:100px;border:solid;';
document.body.append(a);

Create multiple elements

  • You can add several elements to the document.body.
  • You can add elements to other elements.
  • Change this code to match the model answer
  • Can you see why the flag does not show?
let a = document.createElement('div');
a.innerHTML = 'Germany, ';
let b = document.createElement('i');
b.innerHTML = 'Berlin';
a.appendChild(b);
document.body.append(a);
let c = document.createElement('img');
c.src = '/flags/de.png';
c.style = 'width:100px';
let a = document.createElement('div');
a.innerHTML = 'Germany, ';
let b = document.createElement('i');
b.innerHTML = 'Berlin';
a.append(b);
document.body.appendChild(a);
let c = document.createElement('img');
c.src = '/flags/de.png';
c.style = 'width:100px';
document.body.append(c);

Setting complex innerHTML

You can put more complex HTML into an element. The backticks ` ` can span many lines.

Make the flags bigger - you can set the height to 2ex
let a = document.createElement('div');
a.innerHTML = `
  <img src='/flags/gr.png' style='height:1ex'>
  Greece <i>Athens</i>`;
document.body.appendChild(a);
let b = document.createElement('div');
b.innerHTML = `
  <img src='/flags/it.png' style='height:1ex'>
  Italy <i>Rome</i>`;
document.body.appendChild(b);
let a = document.createElement('div');
a.innerHTML = `
  <img src='/flags/gr.png' style='height:2ex'>
  Greece <i>Athens</i>`;
document.body.appendChild(a);
let b = document.createElement('div');
b.innerHTML = `
  <img src='/flags/it.png' style='height:2ex'>
  Italy <i>Rome</i>`;
document.body.appendChild(b);

Using functions

  • You should avoid copying chunks of code.
  • A well chosen function can help avoid that.
  • Notice how string interpolation allows you to include variables in the string.
function addCountryDiv(name, capital, flag){
  let a = document.createElement('div');
  a.innerHTML = `
    <img src='/flags/${flag}.png'
         style='height:2ex;'>
    ${name}`;
  document.body.appendChild(a);
}

addCountryDiv('China', 'Beijing', 'cn');
addCountryDiv('Japan', 'Tokyo', 'jp');
addCountryDiv('South Korea', 'Seoul', 'kr');
function addCountryDiv(name, capital, flag){
  let a = document.createElement('div');
  a.innerHTML = `
    <img src='/flags/${flag}.png'
         style='height:2ex;border:solid'>
    ${name} <i>${capital}</i>`;
  document.body.appendChild(a);
}

addCountryDiv('China', 'Beijing', 'cn');
addCountryDiv('Japan', 'Tokyo', 'jp');
addCountryDiv('South Korea', 'Seoul', 'kr');