react中剪切图片主要用到react-avatar-editor。用之前要用npm安装一下npm install react-avatar-editor

这篇博客主要是为下一篇博客（React仿微信上传图片预览（可剪切））打下基础的。

主要代码如下：

<AvatarEditor ref={this.setEditorRef} image={this.state.originImg} width={400} height={400} border={100} color={[248, 249, 250, 0.8]} borderRadius={200} scale={parseFloat(this.state.scale)} style={{ margin: '0 50px' }} />

import React from 'react'
import AvatarEditor from 'react-avatar-editor'                // 加载 react-avatar-editor
import shopDetailTwo from "./../images/shopDetailTwo.png"
import "./scss/css.css"
import cha from "./../images/cha.png"
class UpImgCom extends React.Component {
    constructor(props, context) {
        super(props, context);
        this.shouldComponentUpdate = PureRenderMixin.shouldComponentUpdate.bind(this);
        this.state={
            originImg:shopDetailTwo,
            loading: false,
            scale:1.2
        }
    }
    onClickSave = () => {
        if (this.editor) {
            const canvas = this.editor.getImage();
            console.log(canvas);
            const canvasScaled = this.editor.getImageScaledToCanvas();
            this.refs.img.src=canvasScaled.toDataURL("image/png");
        }
    }
    setEditorRef = editor => (this.editor = editor);
    render() {
        return (
            <div>
                <div className="upImg">
                    <div className="disDiv"></div>
                    <div className="imgDiv">
                        <p className="editor">编辑头像</p>
                        <div className="cha" onClick={this.hideUpImg}>
                            <img src={cha} />
                        </div>
                        <p className="font">调整头像尺寸和位置</p>
                        <AvatarEditor
                            ref={this.setEditorRef}
                            image={this.state.originImg}
                            width={400}
                            height={400}
                            border={100}
                            color={[248, 249, 250, 0.8]}
                            borderRadius={200}
                            scale={parseFloat(this.state.scale)}
                            style={{  margin: '0 50px' }}
                        />
                        <div className="progressAll clearfloat">
                            <div className="progress" ref="progressAll">
                                <div className="yuan" ref="yuan">
                                    <div></div>
                                </div>
                                <div className="yuanLi"></div>
                                <div className="yuanLi2" ref="yuanLi2"></div>
                                <span>拖动滑块缩放图片</span>
                            </div>
                        </div>
                        <div className="sumbit clearfloat">
                            <div className="quxiao">取消</div>
                            <div className="quedin" onClick={this.onClickSave}>确定</div>
                        </div>
                    </div>
                </div>
                <img src="" ref="img" /> 
            </div>
        )
    }
}

export default UpImgCom