ant-design/components/modal/demo/position.md

order	title
7	[{zh-CN 自定义位置} {en-US To customize the position of modal}]

zh-CN

1.0 之后，Modal 的 align 属性被移除，您可以直接使用 style.top 或配合其他样式来设置对话框位置。

en-US

After release 1.0, Modal's align prop was removed. You can use style.top or other styles to set position of modal dialog.

import { Modal, Button } from 'antd';

class App extends React.Component {
  state = {
    modal1Visible: false,
    modal2Visible: false,
  }
  setModal1Visible(modal1Visible) {
    this.setState({ modal1Visible });
  }
  setModal2Visible(modal2Visible) {
    this.setState({ modal2Visible });
  }
  render() {
    return (
      <div>
        <Button type="primary" onClick={() => this.setModal1Visible(true)}>Display a modal dialog at 20px to Top</Button>
        <Modal
          title="20px to Top"
          style={{ top: 20 }}
          visible={this.state.modal1Visible}
          onOk={() => this.setModal1Visible(false)}
          onCancel={() => this.setModal1Visible(false)}
        >
          <p>some contents...</p>
          <p>some contents...</p>
          <p>some contents...</p>
        </Modal>
        <br /><br />
        <Button type="primary" onClick={() => this.setModal2Visible(true)}>Vertically centered modal dialog</Button>
        <Modal
          title="Vertically centered modal dialog"
          wrapClassName="vertical-center-modal"
          visible={this.state.modal2Visible}
          onOk={() => this.setModal2Visible(false)}
          onCancel={() => this.setModal2Visible(false)}
        >
          <p>some contents...</p>
          <p>some contents...</p>
          <p>some contents...</p>
        </Modal>
      </div>
    );
  }
}

ReactDOM.render(<App />, mountNode);

/* use css to set position of modal */
.vertical-center-modal {
  text-align: center;
  white-space: nowrap;
}

.vertical-center-modal:before {
  content: '';
  display: inline-block;
  height: 100%;
  vertical-align: middle;
  width: 0;
}

.vertical-center-modal .ant-modal {
  display: inline-block;
  vertical-align: middle;
  top: 0;
  text-align: left;
}

/*
// Use flex which not working in IE
.vertical-center-modal {
  display: flex;
  align-items: center;
  justify-content: center;
}

.vertical-center-modal .ant-modal {
  top: 0;
}
*/