vue使用pdf.js预览pdf文件的方法

axios({
                method: 'get',
                url:url,
                headers: {
                    "token":auth,
                },
                responseType: 'blob',
            }).then(response => {
                type_ = type_.toLowerCase();
                if (type_ == "docx") {
                    that._type_ = "application/vnd.openxmlformats-officedocument.wordprocessingml.document"
                } else if (type_ == "doc") {
                    that._type_ = "application/msword"
                } else if (type_ == "gif") {
                    that._type_ = "image/gif"
                } else if (type_ == "jpeg" || type_ == "jpg") {
                    that._type_ = "image/jpeg"
                } else if (type_ == "png") {
                    that._type_ = "image/png"
                } else if (type_ == "pdf") {
                    that._type_ = "application/pdf"
                } else if (type_ == "txt") {
                    that._type_ = "text/plain;charset=utf-8'"
                } else if (type_ == "xls") {
                    that._type_ = "application/vnd.ms-excel" 
                } else if (type_ == "xlsx") {
                    that._type_ = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
                }else if (type_ == "zip") {
                    that._type_ = "application/zip"
                } else if (type_ == "ppt") {
                    that._type_ = "application/vnd.ms-powerpoint"
                } else if (type_ == "pptx") {
                    that._type_ = "application/vnd.openxmlformats-officedocument.presentationml.presentation"
                }
               if(type_ == "pdf"){
                    var blob = new Blob([response.data], { type: that._type_ })
                    var href = window.URL.createObjectURL(blob); //创建下载的链接
                    window.open("/build/generic/web/viewer.html?file="+href);
                }
            })