How to Implement Multicolor Text Highlighting in Text Editors?

Multicolor Text Highlighting in Text Editors

To introduce multicolored text highlighting in textarea or text input elements, you'll primarily need to delve into the realms of JavaScript and CSS. However, it's important to note that these elements do not inherently support text highlighting with different colors.

For syntax highlighting functionality, you'll need to utilize:

Editable Element: Employ contenteditable elements or contenteditable attributes on existing HTML elements to enable users to edit the text content.

JavaScript:

• Utilize JavaScript to identify the keywords that need to be highlighted.
• Create and append span elements with appropriate color classes to the targeted keywords.

CSS:

• Establish color classes in your CSS to control the highlight colors for the various keywords.

Example (in JavaScript and CSS):

<code class="js">// Here's the JavaScript code
const keywords = ["var", "if", "else", "for"]; // Your list of keywords
const textarea = document.getElementById("textarea");

textarea.addEventListener("input", (e) => {
  const start = textarea.selectionStart;
  const end = textarea.selectionEnd;
  const text = textarea.value.substring(start, end);

  if (keywords.includes(text)) {
    // Apply highlighting to the selected text
    textarea.value = textarea.value.substring(0, start)
      + "<span class='highlight'>" + text + "</span>"
      + textarea.value.substring(end);
  }
});</code>

<code class="css">/* CSS for syntax highlighting*/
.highlight {
  color: red;
  font-weight: bold;
}</code>

Working with editable elements (as opposed to textarea or text inputs) provides greater flexibility in applying multicolored text highlighting.

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