react utif tif格式图片预览

1、npm install @types/utif --save-dev

2、import { decode, decodeImage,toRGBA8} from 'utif';

3、

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export const GetFile = (url: string, id: string, type?: number) => {   return new Promise(function (resolve, reject) {     var xhr = new XMLHttpRequest();     url += '?id=' + id + '';     xhr.open('GET', url, true);     xhr.responseType = 'arraybuffer';     xhr.onload = (e) => {       if (xhr.status === 200) {         try {           let imgInfo = decode(xhr.response)[0];           decodeImage(xhr.response,imgInfo);           let imgToRGBA8 = toRGBA8(imgInfo);           var canvas = document.createElement('canvas');           var context = canvas.getContext('2d');           canvas.width = imgInfo.width;           canvas.height =imgInfo.height;           var imageData = context.createImageData(imgInfo.width, imgInfo.height);           imageData.data.set(imgToRGBA8);           context.putImageData(imageData, 0, 0);           let result=canvas.toDataURL("image/png");           resolve(result);           } catch (error) {           reject(new Error(error));         }       } else {         reject(new Error('图片获取失败'));       }     };     xhr.send();   }).catch((e) => {     return e;   }); };