URL预览functionpreviewPdf(url,filename){window.open(url,filename,`width=1060,height=${screen.height},left=${(screen.width-1060)>>1}`)}PDF文件预览functionobjectURL2Blob(url){returnnewPromise((resolve)=>{letxhr=newXMLHttpRequest()xhr.open('GET',url,true)xhr.responseType='blob'xhr.onload=function(){if(this.status==200)resolve(this.response)}xhr.send()})}//预览pdf文件异步函数previewPdfFile(file){leturl=URL.createObjectURL(file)letblob=newBlob([awaitobjectURL2Blob(url)],{type:'application/pdf'})url=URL.createObjectURL(blob)previewPdf(url,'JavaScript权力指南.pdf')}//选择pdf文件函数fileSelect(){returnnewPromise((resolve)=>{constinput=document.createElement('input')input.accept='.pdf'input.type='file'input.onchange=()=>{resolve(input.files)}input.click()})}//选择PDF文件预览fileSelect().then((files)=>;{previewPdfFile(files[0])})一些浏览器可能不支持
