Category: jQuery

Sometimes, we want to list all bindings of an element with JavaScript.

In this article, we’ll look at how to list all bindings of an element with JavaScript.

List All Bindings of an Element with JavaScript

To list all bindings of an element with JavaScript, we can use the _data method.

For instance, if we have the following input:

<input>

Then we can write:

const input = $('input')
input.bind('click', () => {})
input.bind('input', () => {})
$.each($._data($(input)[0], 'events'), (i, e) => {
  console.log(i, e);
});

to get the input with $('input').

Then we add the event handlers with:

input.bind('click', () => {})
input.bind('input', () => {})

Next, we get the event handler bindings with:

$._data($(input)[0], 'events')

Then we use the $.each method to loop through the bindings returned by $._data.

In the callback, i is the event name string and e has the event data,

Conclusion

To list all bindings of an element with JavaScript, we can use the _data method.

Sometimes, we want to check if an input field is required using JavaScript.

In this article, we’ll look at how to check if an input field is required using JavaScript.

Check if an Input Field is Required Using JavaScript

To check if an input field is required using JavaScript, we can check if the required attribute of each input field is set.

For instance, if we have:

<form id="register">
  <label>Nickname:</label>
  <input type="text" name="name" required="" />
  <br>

  <label>Email:</label>
  <input type="email" name="email" required="" />
  <br>

  <label>Password:</label>
  <input type="password" name="password" required="" />
  <br>

  <label>Again:</label>
  <input type="password" name="password-test" required="" />
  <br>

  <input type="submit" value="Register" />
</form>

Then we write:

$('form#register').find('input').each(function() {
  if (!$(this).prop('required')) {
    console.log("not required");
  } else {
    console.log("required");
  }
});

We have a form that has a few input elements.

Then we get all the input elements in the form with $('form#register').find('input').

Next, we call each with a callback that gets the value of the required attribute with:

$(this).prop('required')

And we negate that to check if a field isn’t required.

If the required attribute isn’t present, then we log 'not required'.

Otherwise, we log 'required'.

Conclusion

To check if an input field is required using JavaScript, we can check if the required attribute of each input field is set.

Sometimes, we want to set margin CSS properties with JavaScript.

In this article, we’ll look at how to set margin CSS properties with JavaScript.

Set Margin CSS Properties with JavaScript

To set margin CSS properties with JavaScript, we can call the css method to change the margin CSS properties.

For instance, if we have the following HTML:

<div>
  hello
</div>

Then we write:

$('div').css('margin-left', '100px');

to select the div with $('div').

Then we call the css method on the returned div jQuery object with the property key and value we want to set respectively.

Therefore, we set margin-left to 100px.

The unit must be included.

Now we should see a 100px left margin added to the div.

Conclusion

To set margin CSS properties with JavaScript, we can call the css method to change the margin CSS properties.

Sometimes, we want to determine the pixel length of a string in JavaScript.

In this article, we’ll look at how to determine the pixel length of a string in JavaScript.

Determine the Pixel Length of a String in JavaScript

To determine the pixel length of a string in JavaScript, we can put the string in a span and then use the jQuery width method to determine the width of the span.

For instance, we can write the following HTML:

<span></span>

Then we can write:

const span = document.querySelector('span')  
span.innerText = 'Here is my string'  
console.log($(span).width())

to get the span width document.querySelector .

And then we set innerText to the string of the span.

Finally, we log the span’s width that we get from $(span).width() from jQuery.

The console log should log 111.

Conclusion

To determine the pixel length of a string in JavaScript, we can put the string in a span and then use the jQuery width method to determine the width of the span.

Sometimes, we want to determine the pixel length of a string in JavaScript.

In this article, we’ll look at how to determine the pixel length of a string in JavaScript.

Determine the Pixel Length of a String in JavaScript

To determine the pixel length of a string in JavaScript, we can put the string in a span and then use the jQuery width method to determine the width of the span.

For instance, we can write the following HTML:

<span></span>

Then we can write:

const span = document.querySelector('span')  
span.innerText = 'Here is my string'  
console.log($(span).width())

to get the span width document.querySelector .

And then we set innerText to the string of the span.

Finally, we log the span’s width that we get from $(span).width() from jQuery.

The console log should log 111.

Conclusion

To determine the pixel length of a string in JavaScript, we can put the string in a span and then use the jQuery width method to determine the width of the span.