Placeholder in IE9

javascript

cross-browser-compatibility

polyfills

javascript-techniques

byAlex Kataev·Dec 11, 2024

To enable placeholders in IE9, use a JavaScript polyfill to emulate native functionality. Here's the script for immediate implementation:

if (!('placeholder' in document.createElement('input'))) { // if(!magic) Do your own!
  var inputs = document.getElementsByTagName('input');
  for (var i = 0; i < inputs.length; i++) {
    (function(input) {
      var placeholderText = input.getAttribute('placeholder'); // asigning the magic words
      if (placeholderText) {
        input.value = placeholderText; // voila, placeholder appeared!
        input.onfocus = function() { if (this.value === placeholderText) this.value = ''; }; // clear 'em all, user's here
        input.onblur = function() { if (this.value === '') this.value = placeholderText; }; // bring 'em back, user left
        input.onblur(); // let's start clean
      } // it's like magic but in input!
    })(inputs[i]);
  }
}

This script will immediately bring the placeholder functionality to IE9's inputs.

Feature compatibility

Cross-browser compatibility is a challenge. Apply feature detection and fallbacks for consistent placeholder support:

Involve Modernizr to detect placeholder attribute support:

if (!Modernizr.input.placeholder) { // no native placeholder support? No worries.
  // enter the polyfill
}

Apply Mathias Bynens's HTML5 Placeholder jQuery Plugin for a comprehensive solution:

$('input, textarea').placeholder(); // "Let there be placeholder", and there was placeholder.

Manage dynamic content by binding the polyfill to events that manipulate the DOM:

$(document).on('DOMNodeInserted', function(e) { // node insertion, a life event for a DOM element!
  $(e.target).find('input, textarea').placeholder(); // don't forget the placeholders, they have feelings too.
});

Placeholder aesthetics and usability

Enhance user experience with refined placeholder visuals and interactive capabilities:

Implement CSS classes to mimic placeholders in browsers not supporting native styling.
Ensure placeholders are cleared during form submission to prevent submission of placeholder text.
Deliver the polyfill selectively to IE versions needing it using conditional comments, optimising browser performance.
Ensure consistency by utilizing class changes to achieve a uniform look across different browsers.

Handling form elements

Consider all aspects of form details to improve user interaction:

Bring the placeholder functionality to textarea elements in addition to input tags.
Customize event actions for specific behaviors, depending on the form's level of complexity and user requirements.
Prioritize accessibility and user experience in shaping loose and straightforward placeholder operations.

Testing

Corroborate the validity of placeholders across different platforms and scenarios:

Validate cross-browser compatibility and user interactions with stationed and dynamic placeholders.
Monitor for unexpected behaviour like a static cursor or unresponsiveness.
Involve automated tools such as Selenium for regression testing to ensure continued placeholder functionalty.

Code readability

Structure your JavaScript code for better legibility and maintainability:

Use comprehensive comments in code snippet for clarity, questions, possible pitfalls and Reddit-style humour.
Isolate placeholder functionalities into separate, reusable functions.
Prioritize accessibility by providing adequate visual cues and text contrast for visually-impaired users.