HarmonyOS 创建X509Cert报错

创建X512Cert报错。

readStringFromFile(AppUtil.getAppPath() + '/iip.pem').then(res => {
  if (res == null || res == '' || res.length == 0) {
  } else {
    let encodingBlob: certFramework.EncodingBlob = {
      data: this.stringToUint8Array(res),
      encodingFormat: certFramework.EncodingFormat.FORMAT_PEM
    };
    certFramework.createX509Cert(encodingBlob, (err, x509Cert) => {
      if (err) {
      } else {
        AppStorage.set(AppConst.Cert, x509Cert)
      }
    });
  }
})

err报无法创建X509Cert。