仅当选择新图像时，我的代码才有效。但我想裁剪并保存现有图像

Question

我的代码仅在选择新图像时才有效。但我也想裁剪并保存现有图像。我正在使用react-avatar-edit。

import React from 'react';
import Avatar from 'react-avatar-edit';

class CropAndDrop extends React.Component {
    constructor(props) {
        super(props);

        const src = 'http://i65.tinypic.com/2gwz5s8.jpg';
        this.state = {
            preview: null,
            src,
        };
    }

    onClose = () => {
        this.setState({ preview: null });
    };

    onCrop = preview => {
        this.setState({ preview });
        let tempImage = this.state.preview;
        this.props.preserveImage(tempImage);
        // localStorage.setItem('tempImage', this.state.preview);
        // localStorage.getItem('tempImage');
    };

    render() {
        return (
            <div>
                <Avatar
                    width={600}
                    height={395}
                    onCrop={this.onCrop}
                    onClose={this.onClose}                  
                    src={this.state.src}

                />
            </div>
        );
    }
}
export default CropAndDrop;