reactjs - What is the proper way to get the mouse position in a React Component? -


i have component renders canvas element. have onmousemove handler, when move mouse towards top of element event.clienty prints 86. why not 0? there synthetic event property give me point relative element's coordinate system , not windows?

you can use targets offsettop relative position subtracting clienty like

event.clienty - event.target.offsettop

you can see example

class app extends react.component{    render(){      return(        <div>          <div>top component</div>          <div classname="main" onmousemove={(e) => console.log(e.clienty - e.target.offsettop)}>main component</div>        </div>      )    }  }    reactdom.render(<app/>, document.getelementbyid("root"));
div{    min-height: 50px;  }    div.main{    background-color: blue;  }
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>  <script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>  <div id="root"></div>


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