The selectionEnd property of the HTMLInputElement interface is a number that represents the end index of the selected text. When there is no selection, this returns the offset of the character immediately following the current text input cursor position.
Note: According to the WHATWG forms spec selectionEnd property applies only to inputs of types text, search, URL, tel, and password. In modern browsers, throws an exception while setting selectionEnd property on the rest of input types. Additionally, this property returns null while accessing selectionEnd property on non-text input elements.
If selectionEnd is less than selectionStart, then both are treated as the value of selectionEnd.
<label for="color">selectionStart property on type=color</label>
<input id="color" type="color" />
<fieldset>
<legend>selectionEnd property on type=text</legend>
<label for="pin">Input PIN</label>
<input type="text" id="pin" value="impossible PIN: 102-12-145" />
<button id="pin-btn" type="button">PIN correction</button>
</fieldset>
const colorEnd = document.getElementById("color");
const text = document.querySelector("#pin");
const pinBtn = document.querySelector("#pin-btn");
const validPinChecker = /[^\d{3}-\d{2}-\d{3}]/g;
const selectionEnd = text.value.length;
const selectedText = text.value.substring(text.selectionStart, selectionEnd);
pinBtn.addEventListener("click", () => {
const correctedText = selectedText.replace(validPinChecker, "");
text.value = correctedText;
});
console.log(colorEnd.selectionEnd);