Category: JavaScript Answers

Sometimes, we want to insert text in a td with ID using JavaScript.

In this article, we’ll look at how to insert text in a td with ID using JavaScript.

How to insert text in a td with ID using JavaScript?

To insert text in a td with ID using JavaScript, we set the innerHTML property.

For instance, we write

document.getElementById("td1").innerHTML = "Some text to enter";

to select the td element with getElementById.

Then we set its innerHTML property to the text we want to show in the td element.

Conclusion

To insert text in a td with ID using JavaScript, we set the innerHTML property.

Sometimes, we want to listen for the click event for a marker in Leaflet.

In this article, we’ll look at how to listen for the click event for a marker in Leaflet.

How to listen for the click event for a marker in Leaflet?

To listen for the click event for a marker in Leaflet, we can use the on method.

For instance, we write

L.marker([10.496093, -66.881935])
  .addTo(map)
  .on("click", (e) => {
    console.log(e.latlng);
  });

to call L.marker with an array with the longitude and latitude to create a marker.

Then wee call addTo to add it to the map.

And then we call on to add a click listener.

In the click listener, we get the latitude and longitude with e.latlng.

Conclusion

To listen for the click event for a marker in Leaflet, we can use the on method.

Sometimes, we want to remove a child node in HTML using JavaScript.

In this article, we’ll look at how to remove a child node in HTML using JavaScript.

How to remove a child node in HTML using JavaScript?

To remove a child node in HTML using JavaScript, we can use the remove method.

For instance, we write

document.getElementById("FirstDiv").remove();

to select the element with getElementById.

Then we call remove to remove the selected element.

Conclusion

To remove a child node in HTML using JavaScript, we can use the remove method.

Sometimes, we want to check whether a variable is defined in Node.js and JavaScript.

In this article, we’ll look at how to check whether a variable is defined in Node.js and JavaScript.

How to check whether a variable is defined in Node.js and JavaScript?

To check whether a variable is defined in Node.js and JavaScript, we can check if it’s not null or undefined.

For instance, we write

if (typeof query !== "undefined" && query !== null) {
  doStuff();
}

to check if query isn’t undefined with typeof query !== "undefined".

And we check if query isn’t null with query !== null.

Conclusion

To check whether a variable is defined in Node.js and JavaScript, we can check if it’s not null or undefined.

Sometimes, we want to find all indexes of a specified character within a string with JavaScript.

In this article, we’ll look at how to find all indexes of a specified character within a string with JavaScript.

How to find all indexes of a specified character within a string with JavaScript?

To find all indexes of a specified character within a string with JavaScript, we can use the string matchAll method.

For instance, we write

const string = "scissors";
const matches = [...string.matchAll(/s/g)];
const indexes = matches.map((match) => match.index);

to call string.matchAll with a regex to find all instances of 's' in string.

Then we call matches.map with a callback that gets the index property of each match object to get the index of each match in a new array and return it.

Conclusion

To find all indexes of a specified character within a string with JavaScript, we can use the string matchAll method.