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Editor to share with you what the vector layer structure in TE development is like, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

In the development process of the system, we sometimes manipulate the objects in the vector layer, such as querying an object in the layer for positioning, highlighting the objects in the layer, and so on. Then we need to traverse the layer to understand the structure of the vector layer in TE development.

Note: there is a limit to the vector data loaded in TE. The objects in the vector layer can be searched only if they are displayed in TE, so this often leads to fewer layers obtained by TE than directly viewing the data in the source data.

In the development, you can use the GetLayer method of IProjectTree to obtain the layer, and the returned interface is IFeatureLayer, which is the object interface of the vector layer, and you can get some common properties of the layer, such as DataSourceInfo,GeometryType, etc., corresponding to the right-click on the TE layer attribute information.

IFeatureLayer attributes in FeatureGroups, is the layer contains the feature set, the number of FeatureGroups is uncertain, for example, there is a collection of lines, there is only one, if there is another annotated layer, there will be two, if different geometric types, there may be more, so, in the development, to be sure.

The next level of FeatureGroups is FeatureGroup, which can be obtained in two ways, such as knowing the collection type of layers, FeatureGroups.Point/Polyline/Polygon can get the collection layer directly, FeatureGroups.Annotation can get the annotation layer directly, and the other way is to use the index to write FeatureGroups (0) in js and FeatureGroups [0] in C #, which requires a good order of layers.

Some layer style properties can be set in FeatureGroup, using the

GetCurrentFeatures can get the feature objects loaded in the current TE, and the returned result is IFeatures, which is the case mentioned above, not all the objects in the source data of the layer. IFeatures is a collection of feature objects, which can obtain the number of all objects. By writing as IFeatures (0) in js and IFeatures [0] in C #, we can get a single object IFeature. IFeature is a single feature object. At this point, the feature object in the layer has been obtained. There is attribute information FeatureAttributes in the feature object, which contains the attribute information of the current object. The attribute information is queried when the attributes can be displayed in TE, which varies according to different data.

The GetFeatureAttribute in IFeatureAttributes can get the data in this column of the current object based on the table column name in the property. These are all the contents of this article entitled "what is the structure of vector layers in TE development?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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