Question: I want to let user add another input file immediately next down the button, so he can select and send "x" number of files 

[![image](https://i.stack.imgur.com/TI4eJ.png)](https://i.stack.imgur.com/TI4eJ.png)

Ive been using these answers while searching with no luck

```
http://stackoverflow.com/a/19200323/5586647
http://stackoverflow.com/a/19200278/5586647
http://stackoverflow.com/a/30098596/5586647

```

piece of my code where I want to insert new tr is

```
echo '<tr align=center ><td colspan="4"><input type="file" name="oc" id="oc"/></td><td><input type="button" value="add more" id="addme"/></td></tr>';

```

I would aprecciate a bit of help

**EDIT:**

While using the answers I got an issue that adds de tr (or I guess is a tr) but to a side of the original (using append)

[![enter image description here](https://i.stack.imgur.com/GGglV.png)](https://i.stack.imgur.com/GGglV.png)

and what I want is:

[![enter image description here](https://i.stack.imgur.com/NoKgE.png)](https://i.stack.imgur.com/NoKgE.png)

CODE: <https://jsfiddle.net/9k4kmvmw/>

Answer: 
I've found the error. 
I'm initializing the Provider with an empty object, and should be initialized with an empty array. So

`clusterProvider = new H.clustering.Provider({});` 

should be 

`clusterProvider = new H.clustering.Provider([]);`

Question is, should it be allowed to initialize the provider with the wrong set of data? or should it return an error?
In my case, it was not allowing me to initialize cluster provider like without clusteringOptions, but when I provided clusteringOptions is worked :

```
clusterProvider = new H.clustering.Provider([], {
      clusteringOptions: {
        eps: 32,
        minWeight: 2
      }
    });

```