Category: JavaScript Answers

Sometimes, we want to programmatically force an onchange event on an input with JavaScript.

In this article, we’ll look at how to programmatically force an onchange event on an input with JavaScript.

How to programmatically force an onchange event on an input with JavaScript?

To programmatically force an onchange event on an input with JavaScript, we use the Event constructor.

For instance, we write

const element = document.getElementById("input");
const event = new Event("change");
element.dispatchEvent(event);

to call getElementById to select the input element.

Then we create a new Event object that triggers the change event.

And then we call element.dispatchEvent with event to trigger the change event.

Conclusion

To programmatically force an onchange event on an input with JavaScript, we use the Event constructor.

Sometimes, we want to convert hyphens to camel case with JavaScript.

In this article, we’ll look at how to convert hyphens to camel case with JavaScript.

How to convert hyphens to camel case with JavaScript?

To convert hyphens to camel case with JavaScript, we can use the string replace method.

For instance, we write

const camelCased = myString.replace(/-([a-z])/g, (g) => {
  return g[1].toUpperCase();
});

to call myString.replace with a regex that matches a letter before hyphen and a callback that returns the replacement for the match.

We use -([a-z]) to match a hyphen with a lower case letter after it.

And we use the g flag to return all matches.

Conclusion

To convert hyphens to camel case with JavaScript, we can use the string replace method.

Sometimes, we want to delete a query string parameter in JavaScript.

In this article, we’ll look at how to delete a query string parameter in JavaScript.

How to delete a query string parameter in JavaScript?

To delete a query string parameter in JavaScript, we can use the URLSearchParams constructor.

For instance, we write

const params = new URLSearchParams("param1=1&param2=2&param3=3");
console.log(params.toString());
params.delete("param2");
console.log(params.toString());

to pass in the query string into the URLSearchParams constructor.

Then we call delete on the params object to remove the query parameter with key 'param2'.

Then we convert the params object to a string with toString.

Conclusion

To delete a query string parameter in JavaScript, we can use the URLSearchParams constructor.

Sometimes, we want to use .join method to convert array to string without commas with JavaScript.

In this article, we’ll look at how to use .join method to convert array to string without commas with JavaScript.

How to use .join method to convert array to string without commas with JavaScript?

To use .join method to convert array to string without commas with JavaScript, we call it with an empty string.

For instance, we write

const s = arr.join("")

to call join on the arr array with an empty string to join the strings in arr without commas.

Conclusion

To use .join method to convert array to string without commas with JavaScript, we call it with an empty string.

Sometimes, we want to convert XML to JSON and back using JavaScript.

In this article, we’ll look at how to convert XML to JSON and back using JavaScript.

How to convert XML to JSON and back using JavaScript?

To convert XML to JSON and back using JavaScript, we can use the txml package.

To install it, we run

npm i txml

Then we use it by writing

const xml = require("txml");
const data = `
<tag>tag content</tag>
<tag2>another content</tag2>
<bar>
  <foo>inside content</foo>
  <emptyTag />
</bar>`;

const dom = xml(data);
xml.stringify(dom);

const json = xml.parse(data);

to call xml with the data XML string to convert it to a DOM object.

And we call xml.stringify to convert the dom object back to an XML string.

We call xml.parse with data to convert the XML string to a JavaScript object.

Conclusion

To convert XML to JSON and back using JavaScript, we can use the txml package.