OpenLayers4 / JavaScript：XmlPullParserException

Question

我已经创建了一个矢量层，并在网页上在其上绘制了一个多边形，现在，我想将该多边形插入到geoserver上的wms图像层中。使用以下代码：

var node;
        var lName = 'myworkspace:mylayer, http://*.*.*.*:8080/geoserver';
        var layerAuth = "-";
        var lNameInfo = lName.split(',');
        var url = lNameInfo[1];
        var layer = lNameInfo[0];
        //console.log(layer.split(':')[0]);
        var formatWFS = new ol.format.WFS();
        var formatGML = new ol.format.GML({           
            featureNS: url + '/' + layer.split(':')[0],
            featureType: layer.split(':')[1],
            srsName: 'EPSG:28191'
        });


        var xs = new XMLSerializer();


        var featureProperties = f.getProperties();
        var clone = new ol.Feature(featureProperties);

        //clone.setId(layer.split(':')[1] + "." + "7");
        //(Math.floor(Math.random() * 90000) + 10000)
        switch (p) {
            case 'insert':
                node = formatWFS.writeTransaction([clone], null, null, formatGML);
                break;
        }

        var payload = xs.serializeToString(node);
        var req = payload.replace('geometry', 'Shape').replace('/geometry', '/Shape').replace('typeName="feature:', 'typeName="' + layer.split(':')[0] + ':');
        //console.log(req);
        alert(payload);
        alert(req);

        $.ajax(url + "/wfs", {
            type: 'POST',
            dataType: 'xml',
            processData: false,
            contentType: 'text/xml',
            data: { url: url + "/wfs", xml: payload, auth: layerAuth },
            success: function (result) {
                //console.log(result);
                if ($(result).find("HttpError").length > 0) {
                    alert('error');
                    toastr.error($(result).find("HttpError").text().trim());
                } else {
                    if ($(result).find("ows\\:ExceptionReport").length > 0) {
                        toastr.error($(result).find("ows\\:ExceptionReport").text().trim());
                        alert($(result).find("ows\\:ExceptionReport").text().trim());
                    } else {
                        toastr.success("Feature Geometry Inserted Successfully");
                        alert('success');
                    }
                }
            }
        }).done(function () {
           // sourceWFS.clear();
            });

此代码为我提供了以下异常：

org.xmlpull.v1.xmlpullparserexception only whitespace content allowed 

有什么主意吗？???

这是req变量的内容：

<Transaction xmlns="http://www.opengis.net/wfs" service="WFS" version="1.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/wfs http://schemas.opengis.net/wfs/1.1.0/wfs.xsd"><Insert><mylayer xmlns=" http://*.*.*.*:8080/geoserver/myworkspace"><Shape><Polygon xmlns="http://www.opengis.net/gml" srsName="EPSG:28191"><exterior><LinearRing srsName="EPSG:28191"><posList srsDimension="2">3905141.4998611817 3703192.482474612 3905471.1345456615 3703211.5917316834 3905361.2563175014 3702967.9487040243 3905141.4998611817 3703192.482474612</posList></LinearRing></exterior></Polygon></Shape></mylayer></Insert></Transaction>