一直报：Required request part 'file' is not present
postman（测试工具）

我的代码
foreach (const QFileInfo info, QDir(path).entryInfoList()) {
QString name = info.fileName(); //文件名
if (!name.startsWith("YT")) {
continue;
}
ui->textEdit->append("读取到图片:" + name);

//param
QJsonObject object;
QString expressNumber = name.section(QChar('_'), 0, 0);
object.insert("expressNumber", expressNumber);
object.insert("nameNumber", "574901"); //网点代号
object.insert("opCode", "182"); //操作代码
object.insert("snNumber", mac); //设备编码
object.insert("imgSource", info.filePath()); //图片来源
object.insert("extend", "");
QByteArray param = QJsonDocument(object).toJson();
qDebug() append("param:" + param);

//signature
int length = param.length();
QString str = QString::asprintf("%08d", length);
qDebug() append("param长度" + str);
QString str1 = str + param;
QCryptographicHash cryptographic(QCryptographicHash::Md5);
cryptographic.addData(str1.toLocal8Bit());
QByteArray signature = cryptographic.result().toHex();
ui->textEdit->append("signature:" + signature);

QHttpMultiPart *multiPart = new QHttpMultiPart(
QHttpMultiPart::FormDataType);

QHttpPart paramPart;
paramPart.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("text/plain"));
paramPart.setHeader(QNetworkRequest::ContentDispositionHeader,
QVariant("form-data;name=\"param\""));
paramPart.setBody(param);

QHttpPart signaturePart;
signaturePart.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("text/plain"));
signaturePart.setHeader(QNetworkRequest::ContentDispositionHeader,
QVariant("form-data;name=\"signature\""));
paramPart.setBody(signature);

QHttpPart imagePart;
imagePart.setHeader(QNetworkRequest::ContentTypeHeader,
QVariant("image/jpeg"));
imagePart.setHeader(QNetworkRequest::ContentDispositionHeader,
QString("form-data; name=\"file\"; filename=\"" + info.filePath() + "\""));
QFile *file = new QFile(info.filePath());
bool open = file->open(QIODevice::ReadOnly);
ui->textEdit->append(QString("文件打开：%1").arg(open));
imagePart.setBodyDevice(file);
file->setParent(multiPart);

multiPart->append(imagePart);
multiPart->append(signaturePart);
multiPart->append(paramPart);

QNetworkAccessManager manager;
QNetworkRequest request;
request.setUrl(QUrl(url1));
qDebug() setParent(reply);
QEventLoop loop(this);
connect(&manager, &QNetworkAccessManager::finished,
&loop, &QEventLoop::quit);
connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),
this, SLOT(upLoadError(QNetworkReply::NetworkError)));
loop.exec();

哎，死活不成功啊！！！