Detect Caps Lock with JavaScript

Date:


Anyone is capable of having their caps lock key on at any given time without realizing so. Users can easily spot unwanted caps lock when typing in most inputs, but when using a password input, the problem isn’t so obvious. That leads to the user’s password being incorrect, which is an annoyance. Ideally developers could let the user know their caps lock key is activated.

To detect if a user has their keyboard’s caps lock turn on, we’ll employ KeyboardEvent‘s getModifierState method:

document.querySelector('input[type=password]').addEventListener('keyup', function (keyboardEvent) {
    const capsLockOn = keyboardEvent.getModifierState('CapsLock');
    if (capsLockOn) {
        // Warn the user that their caps lock is on?
    }
});

I’d never seen getModifierState used before, so I explored the W3C documentation to discover other useful values:

dictionary EventModifierInit : UIEventInit {
  boolean ctrlKey = false;
  boolean shiftKey = false;
  boolean altKey = false;
  boolean metaKey = false;

  boolean modifierAltGraph = false;
  boolean modifierCapsLock = false;
  boolean modifierFn = false;
  boolean modifierFnLock = false;
  boolean modifierHyper = false;
  boolean modifierNumLock = false;
  boolean modifierScrollLock = false;
  boolean modifierSuper = false;
  boolean modifierSymbol = false;
  boolean modifierSymbolLock = false;
};

getModifierState provides a wealth of insight as to the user’s keyboard during key-centric events. I wish I had known about getModifier earlier in my career!

  • JavaScript Promise API

    While synchronous code is easier to follow and debug, async is generally better for performance and flexibility. Why “hold up the show” when you can trigger numerous requests at once and then handle them when each is ready?  Promises are becoming a big part of the JavaScript world…

  • Convert XML to JSON with JavaScript


Source link

Share post:

[tds_leads title_text="Subscribe" input_placeholder="Email address" btn_horiz_align="content-horiz-center" pp_checkbox="yes" pp_msg="SSd2ZSUyMHJlYWQlMjBhbmQlMjBhY2NlcHQlMjB0aGUlMjAlM0NhJTIwaHJlZiUzRCUyMiUyMyUyMiUzRVByaXZhY3klMjBQb2xpY3klM0MlMkZhJTNFLg==" f_title_font_family="653" f_title_font_size="eyJhbGwiOiIyNCIsInBvcnRyYWl0IjoiMjAiLCJsYW5kc2NhcGUiOiIyMiJ9" f_title_font_line_height="1" f_title_font_weight="700" f_title_font_spacing="-1" msg_composer="success" display="column" gap="10" input_padd="eyJhbGwiOiIxNXB4IDEwcHgiLCJsYW5kc2NhcGUiOiIxMnB4IDhweCIsInBvcnRyYWl0IjoiMTBweCA2cHgifQ==" input_border="1" btn_text="I want in" btn_tdicon="tdc-font-tdmp tdc-font-tdmp-arrow-right" btn_icon_size="eyJhbGwiOiIxOSIsImxhbmRzY2FwZSI6IjE3IiwicG9ydHJhaXQiOiIxNSJ9" btn_icon_space="eyJhbGwiOiI1IiwicG9ydHJhaXQiOiIzIn0=" btn_radius="3" input_radius="3" f_msg_font_family="653" f_msg_font_size="eyJhbGwiOiIxMyIsInBvcnRyYWl0IjoiMTIifQ==" f_msg_font_weight="600" f_msg_font_line_height="1.4" f_input_font_family="653" f_input_font_size="eyJhbGwiOiIxNCIsImxhbmRzY2FwZSI6IjEzIiwicG9ydHJhaXQiOiIxMiJ9" f_input_font_line_height="1.2" f_btn_font_family="653" f_input_font_weight="500" f_btn_font_size="eyJhbGwiOiIxMyIsImxhbmRzY2FwZSI6IjEyIiwicG9ydHJhaXQiOiIxMSJ9" f_btn_font_line_height="1.2" f_btn_font_weight="700" f_pp_font_family="653" f_pp_font_size="eyJhbGwiOiIxMyIsImxhbmRzY2FwZSI6IjEyIiwicG9ydHJhaXQiOiIxMSJ9" f_pp_font_line_height="1.2" pp_check_color="#000000" pp_check_color_a="#ec3535" pp_check_color_a_h="#c11f1f" f_btn_font_transform="uppercase" tdc_css="eyJhbGwiOnsibWFyZ2luLWJvdHRvbSI6IjQwIiwiZGlzcGxheSI6IiJ9LCJsYW5kc2NhcGUiOnsibWFyZ2luLWJvdHRvbSI6IjM1IiwiZGlzcGxheSI6IiJ9LCJsYW5kc2NhcGVfbWF4X3dpZHRoIjoxMTQwLCJsYW5kc2NhcGVfbWluX3dpZHRoIjoxMDE5LCJwb3J0cmFpdCI6eyJtYXJnaW4tYm90dG9tIjoiMzAiLCJkaXNwbGF5IjoiIn0sInBvcnRyYWl0X21heF93aWR0aCI6MTAxOCwicG9ydHJhaXRfbWluX3dpZHRoIjo3Njh9" msg_succ_radius="2" btn_bg="#ec3535" btn_bg_h="#c11f1f" title_space="eyJwb3J0cmFpdCI6IjEyIiwibGFuZHNjYXBlIjoiMTQiLCJhbGwiOiIxOCJ9" msg_space="eyJsYW5kc2NhcGUiOiIwIDAgMTJweCJ9" btn_padd="eyJsYW5kc2NhcGUiOiIxMiIsInBvcnRyYWl0IjoiMTBweCJ9" msg_padd="eyJwb3J0cmFpdCI6IjZweCAxMHB4In0="]
spot_imgspot_img

Popular

More like this
Related

How to Stress-Proof Your Relationship This Holiday Season

It’s not uncommon for couples to feel overwhelmed...

Essential PDF Editing Tips For Accountants and Financial Professionals

Accountants and financial professionals deal with many PDF...

Skillet Chicken Thighs – Spend With Pennies

Tender, juicy skillet chicken thighs go from the...