Get or set the cursor position in a text field

Sometimes we need to set the cursor position in a text field programmatically. For instance, when a user switches a text field from read-only to edit mode, we might want the cursor to move automatically to the end of the input. You may have seen this functionality in many inline edit components.

In this post, we'll explore how to get or set the cursor position in a text field using JavaScript.

To find out where the cursor is in a text field, we can use the `selectionStart` property. This property tells us the index of the first selected character in the text field. But if there's no selected text, it tells us the index of the cursor itself.

Here's a code example that demonstrates how to use `selectionStart` to get the cursor position in a text field:

const textField = document.getElementById('text-field');
const cursorPosition = textField.selectionStart;

In this example, we retrieve the text field by its ID and then use the `selectionStart` property to determine the position of the cursor.

To set the cursor position in a text field, we can use the `setSelectionRange()` method. This method takes two parameters: the start and end indexes of the selection.

Check out this example code snippet to see how it's done:

const textField = document.getElementById('text-field');
textField.setSelectionRange(3, 3);

In this example, we grab the text field using its ID and then use the `setSelectionRange()` method to move the cursor to the fourth character.