无法保存然后恢复图形

Can't save and then restore Graphic

我使用sketchViewModel来编辑图层。我有下一个逻辑:

当我从本地存储上传模型并添加到 graphicLayers 时,出现错误:

[esri.core.Accessor] Accessor#set Invalid property value, value needs to be one of 
'esri.geometry.Extent', 'esri.geometry.Multipoint', 'esri.geometry.Point', 'esri.geometry.Polyline', 
'esri.geometry.Polygon', or a plain object that can autocast (having .type = 'extent', 'multipoint',
'point', 'polyline', 'polygon')

[esri.core.Accessor] Accessor#set Invalid property value, value needs to be one of 
'esri.symbols.SimpleFillSymbol', 'esri.symbols.PictureFillSymbol', 'esri.symbols.PictureMarkerSymbol', 
'esri.symbols.SimpleLineSymbol', 'esri.symbols.SimpleMarkerSymbol', 'esri.symbols.TextSymbol', 
'esri.symbols.LabelSymbol3D', 'esri.symbols.LineSymbol3D', 'esri.symbols.MeshSymbol3D', 
'esri.symbols.PointSymbol3D', 'esri.symbols.PolygonSymbol3D', 'esri.symbols.WebStyleSymbol', 
'esri.symbols.CIMSymbol', or a plain object that can autocast (having .type = 'simple-fill', 'picture-
fill', 'picture-marker', 'simple-line', 'simple-marker', 'text', 'label-3d', 'line-3d', 'mesh-3d', 
'point-3d', 'polygon-3d', 'web-style', 'cim')

这是我的代码:

sketchViewModel.on("update", checkGraphicUpdate);

function checkGraphicUpdate(evt) {
    if(evt.state === 'complete'){
        // dispatchRecentChanges(geometryGraphics);
        localStorage.setItem('features', geometryGraphics.toJSON())
    }
}

if(uploadView){
    graphicsLayer.removeAll();

    JSON.parse(localStorage.feautures).forEach(
        function(featureJson){
            graphicsLayer.add(new Graphic(featureJson))}
    );
}

以下是 LocalStorage 中 JSON 中元素的示例:

{"geometry":{"spatialReference":{"wkid":4326},"paths":[[[-111.3, 52.68], [-98,
 49.5], [-93.94, 29.89]]]},"symbol":{"type":"esriSLS","color":
[0,255,0,255],"width":4,"style":"esriSLSSolid"},"attributes":
{"DATA_SOURSE":"3","AVERAGE_DEPTH":"1.2","MATERIAL":"14","PLACINGFORM":"2","MEAS
UREDLENGTH":"12.4","DIAMETER":"6","STREETNAME":"אבן 
עזרא","DIAMETERUNIT":"'אינצ","STATUS":"1","LOCATION":"13","INSTALLYEAR":"2018","
Title":"Water_Pipe_Section [F3FA]","PURPOSE":"1"},"popupTemplate":
{"popupElements":[{"type":"fields","fieldInfos":
[{"fieldName":"DATA_SOURSE","visible":true},
{"fieldName":"AVERAGE_DEPTH","visible":true},
{"fieldName":"MATERIAL","visible":true},
{"fieldName":"PLACINGFORM","visible":true},
{"fieldName":"MEASUREDLENGTH","visible":true},
{"fieldName":"DIAMETER","visible":true},
{"fieldName":"STREETNAME","visible":true},
{"fieldName":"DIAMETERUNIT","visible":true},
{"fieldName":"STATUS","visible":true},{"fieldName":"LOCATION","visible":true},
{"fieldName":"INSTALLYEAR","visible":true},{"fieldName":"Title","visible":true},
{"fieldName":"PURPOSE","visible":true}]}],"title":"{Title}"}}

据我所知,这是由于存储的数据有误造成的。但是如何保存这些数据,然后提取不出错?

发生此错误是因为 geometry.type 和 symbol.type 未保存在 JSON 中。 解决方案是检查 if((data.symbol ['type'] === "esriSLS")) 然后扩展 new Polyline() 并明确指定符号:{type: "simple-line" } 在 new Graphic() 中。

代码:

if (data.symbol['type'] === "esriSLS") {

        const {type, fieldInfos} = popupElements[0],
            {paths} = geometry;

        const pLine = new Polyline({spatialReference, paths});

        const symbol = {
            type: "simple-line",
            width: width,
            color: color
        };

        return new Graphic({
            geometry: pLine,
            symbol: symbol,
            attributes: attributes,
            popupTemplate: {
                title: "{Title}",
                content: [{type, fieldInfos}]
            }
        });
    }

在您上面的代码中,我不确定 geometryGraphics 是指一组图形还是单个图形。也就是说,如果你有 Graphic object, the best way to serialize/deserialize it is using toJSON() and fromJSON()。这样您就不必担心内部 JSON 表示。

var graphic = new Graphic({
  geometry: ...,
  symbol: ...,
  ...
});

var json = graphic.toJSON();
var newGraphic = Graphic.fromJSON(json);