HTMLTableRowElement: insertCell()-Methode

insertCell() insertCell(index) 

<table> <thead> <tr> <th>C1</th> <th>C2</th> <th>C3</th> <th>C4</th> <th>C5</th> </tr> </thead> <tbody> <tr> <td>Cell 1</td> <td>Cell 2</td> </tr> </tbody> </table> <button id="add">Add a cell</button> <button id="remove">Remove last cell</button> <div>This first row has <output>2</output> cell(s).</div> 

table { border-collapse: collapse; } th, td, table { border: 1px solid black; } button { margin: 1em 1em 1em 0; } 

// Obtain relevant interface elements const bodySection = document.querySelectorAll("tbody")[0]; const row = bodySection.rows[0]; // Select the first row of the body section const cells = row.cells; // The collection is live, therefore always up-to-date const cellNumberDisplay = document.querySelectorAll("output")[0]; const addButton = document.getElementById("add"); const removeButton = document.getElementById("remove"); function updateCellNumber() { cellNumberDisplay.textContent = cells.length; } addButton.addEventListener("click", () => { // Add a new cell at the end of the first row const newCell = row.insertCell(); newCell.textContent = `Cell ${cells.length}`; // Update the row counter updateCellNumber(); }); removeButton.addEventListener("click", () => { // Delete the row from the body row.deleteCell(-1); // Update the row counter updateCellNumber(); });