react怎么动态增加节点

KmcDialog.showInstance = function(properties) {
    if (!document.getElementById("KmcDialog")) {
        let props = properties || {};
        let div = document.createElement('div');
        div.setAttribute('id', 'KmcDialog');
        document.body.appendChild(div);
        ReactDOM.render(React.createElement(KmcDialog, props), div);
    }
}

KmcDialog.removeInstance = function() {
    if(document.getElementById("KmcDialog")) {
        document.getElementById('KmcDialog').remove();
    }
}

KmcDialog.showInstance({
    isshow: true
});
KmcDialog.removeInstance();