uni-file-picker @select触发返回的文件流怎么获取

@select触发返回的参数为：
{
"tempFilePaths": ["blob:http://localhost:8081/1a94fa39-e80a-4c21-9d51-6942acc66af6"],
"tempFiles": [{
"cloudPath": "1683182576817_0.jpg",
"extname": "jpg",
"file": {
"cloudPath": "1683182576817_0.jpg",
"fileType": "image",
"lastModified": 1621472892742,
"lastModifiedDate": {},
"name": "33333.jpg",
"size": 34915,
"type": "image/jpeg",
"uuid": 1683182576819,
"webkitRelativePath": ""
},
"fileType": "image",
"image": {
"ob": {
"dep": {
"id": 7093,
"subs": []
},
"value": {
"ob": {
"dep": "Object",
"value": "Object",
"vmCount": 0
}
},
"vmCount": 0
}
},
"name": "33333.jpg",
"path": "blob:http://localhost:8081/1a94fa39-e80a-4c21-9d51-6942acc66af6",
"progress": 0,
"size": 34915,
"status": "ready",
"url": "blob:http://localhost:8081/1a94fa39-e80a-4c21-9d51-6942acc66af6",
"uuid": 1683182576819
}]
}
我想要获取文件流转为base64码，但是现在我不知道哪个是文件流，希望前端大佬们帮帮我