bolb、bloburl、file、base64间的转换bloburl格式：blob格式： Blob {size: 272260, type: 'application/pdf'}size: 272260type: "application/pdf"[[Prototype]]: Blob file格式： base64格式： data:application/pdf;base64,JVBERi0xLjMKJbrfrOAKMyAwIG9iag...1.bloburl转换为file httpReques...