Category: JavaScript

Sometimes, we want to detect shift+enter and generate a new line in text area with JavaScript.

In this article, we’ll look at how to detect shift+enter and generate a new line in text area with JavaScript.

How to detect shift+enter and generate a new line in text area with JavaScript?

To detect shift+enter and generate a new line in text area with JavaScript, we can check for shift and enter key presses in the event object.

For instance, we write

textArea.onKeyPress = (e) => {
  if (e.keyCode === 13 && e.shiftKey) {
    e.preventDefault();
    let start = e.target.selectionStart,
      end = e.target.selectionEnd;
    e.target.vaiue =
      prevState.message.substring(0, start) +
      "\n" +
      prevState.message.substring(end);
  } else if (e.keyCode === 13) {
    e.preventDefault();
  }
};

to check keyCode and shiftKey to see if shift+enter is pressed.

If it is, we call preventDefault to prevent the default behavior.

We then get the cursor’s start and end indexes with selectionStart and selectionEnd.

Then we put the new line in between the start and end with

prevState.message.substring(0, start) + "\n" + prevState.message.substring(end);

Conclusion

To detect shift+enter and generate a new line in text area with JavaScript, we can check for shift and enter key presses in the event object.

Sometimes, we want to use lodash to compare jagged arrays with JavaScript.

In this article, we’ll look at how to use lodash to compare jagged arrays with JavaScript.

How to use lodash to compare jagged arrays with JavaScript?

To use lodash to compare jagged arrays with JavaScript, we can sort the arrays with sort and then use isEqual to compare their contents.

For instance, we write

const array1 = [
  ["a", "b"],
  ["b", "c"],
];
const array2 = [
  ["b", "c"],
  ["a", "b"],
];
_.isEqual(array1.sort(), array2.sort());

to call sort to sort both arrays.

And then we call Lodash’s isEqual function to compare the contents of the sorted arrays.

Conclusion

To use lodash to compare jagged arrays with JavaScript, we can sort the arrays with sort and then use isEqual to compare their contents.

Sometimes, we want to convert a string to JSON object with JavaScript.

In this article, we’ll look at how to convert a string to JSON object with JavaScript.

How to convert a string to JSON object with JavaScript?

To convert a string to JSON object with JavaScript, we can use the JSON.parse method.

For instance, we write

const obj = JSON.parse(string);

to call JSON.parse with the JSON string to convert the JSON string to an object.

Conclusion

To convert a string to JSON object with JavaScript, we can use the JSON.parse method.