Onclick on button is not working in ReactJs

I am working with Reactjs (Nextjs),I put my "css,images,js" files in "public" folder,But my
Menu bar is not showing (onclick is not working),How can i make this working so after click on this button menu will display,Here is my code

<button className="openbtn" onclick="openNav()">
        <img src="images/menu_btn.png" />
</button>

>Solution :

You are sending a string to onClick function, so change your onClick button to this,

onClick={ () => openNav() }