How To Add Table Rows & Cells In Javascript (Simple Examples)

Welcome to a quick tutorial on how to add HTML table rows and cells in Javascript. Need to dynamically update an HTML table using Javascript?

That should cover the basics, but read on for more examples!

ⓘ I have included a zip file with all the source code at the start of this tutorial, so you don’t have to copy-paste everything… Or if you just want to dive straight in.

 

 

TLDR – QUICK SLIDES

Fullscreen Mode – Click Here

 

TABLE OF CONTENTS

 

 

QUICK NOTES

If you spot a bug, feel free to comment below. I try to answer short questions too, but it is one person versus the entire world… If you need answers urgently, please check out my list of websites to get help with programming.

 

EXAMPLE CODE DOWNLOAD

Click here to download all the example source code, I have released it under the MIT license, so feel free to build on top of it or use it in your own project.

 

 

 

1) INSERT ROWS & CELLS

<!-- (A) HTML TABLE -->
<table id="demoA">
  <tr> <td>A</td> <td>B</td> </tr>
</table>

<!-- (B) ADD ROWS CELLS -->
<script>
function addRow (top) {
  // (B1) GET TABLE
  var table = document.getElementById("demoA");

  // (B2) INSERT ROW
  if (top) { var row = table.insertRow(0); }
  else { var row = table.insertRow(); }

  // (B3) INSERT CELLS
  var cell = row.insertCell();
  cell.innerHTML = "AA";
  cell = row.insertCell();
  cell.innerHTML = "BB";
}
</script>
<input type="button" value="Add Bottom" onclick="addRow()">
<input type="button" value="Add Top" onclick="addRow(1)">

Look no further, these are the same steps as the introduction snippet – Get the table, add a row, append the cells. But take extra note:

• By default, insertRow() will insert to the bottom of the table.
• Use insertRow(0) to add to the top of the table instead.

Yes, insertRow() takes in an “insert position” parameter. We can do some simple calculations if you want to insert a row into the middle of the table:

• var pos = Math.ceil(table.rows.length / 2);
• var row = table.insertRow(pos);

 

 

2) MANUAL HTML STRING

<!-- (A) HTML TABLE -->
<table id="demoB">
<tr> <td>A</td> <td>B</td> </tr>
</table>

<!-- (B) ADD ROWS CELLS -->
<script>
function addRow () {
  var table = document.querySelector("#demoB tbody");
  table.innerHTML = "<tr><td>TOP</td><td>AA</td></tr>" + table.innerHTML;
  table.innerHTML += "<tr><td>BOTTOM</td><td>BB</td></tr>";
}
</script>
<input type="button" value="Add Rows" onclick="addRow()">

For you guys who prefer to do it the “manual HTML way”, this is the alternative. But a small word of advice – Directly changing the innerHTML is probably not that good for performance, especially when we have a massive table.

 

 

 

WHICH IS BETTER?

Personally, I am leaning towards the “object-oriented” create new rows and cells way. That is just a lot more convenient and easier, without having a write manual HTML code. But both methods are correct – Use whichever works best for you.

 

LINKS & REFERENCES

• Insert Row – MDN
• Insert Cell – MDN
• How To Delete Table Rows & Cells – Code Boxx

 

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