Identify task: Input polygon into IdentifyParameters

Question

I wish to find all the features within a polygon/circle drawn by my user.

May I know if I should use IdentifyTask

https://developers.arcgis.com/en/javascript/jsapi/identifytask.html

Or is there a more recommended way?

Use Case: User drawn a circle/polygon and it will display all the address within the area.

• Kirk Kuykendall: Are all the features within a single layer in the mapservice?
• seesee: yes, apparently identifytask only return a feature...any help on this?
• Kirk Kuykendall: The Identify task allows you to specify which layers in the mapservice you are interested in, whereas the Query task is for a particular layer.

Answer 1

The solution is to use QueryTask.

https://developers.arcgis.com/en/javascript/jsapi/querytask.html

It accepts a Query

https://developers.arcgis.com/en/javascript/jsapi/query.html

which the a geometry parameter can be input to search for features within the specified criterias.

Using QueryTask.execute(parameters,callback,errback) method. It will return a feature set on onComplete(featureSet) callback.

which contains a property call features

https://developers.arcgis.com/en/javascript/jsapi/featureset.html.

By looping through the features[]. We can get the set of features within the geometry.

Answer 2

You can specify the geometry using the identifyparameters class: https://developers.arcgis.com/en/javascript/jsapi/identifyparameters.html

It will accept any type of geometry, typically you would pass it a point, but you could pass in a polygon that is drawn on the screen.

• seesee: yes but apparently it only return a feature. I am trying to find all the address within a geometry.
• CLJ: It returns an identifyResult, not a feature: developers.arcgis.com/en/javascript/jsapi/identifyresult.html
• seesee: An identified feature. - yes 1 feature only.
• CLJ: I don't think you understand. The identify result does not return a single feature, it returns a identifyresult, which is an object that contains an array of features. The identifytask can query multiple layers and return features from these layers. Perhaps you need to rephrase your question.
• seesee: developers.arcgis.com/en/javascript/jsapi/identifyresult.html in the properties you will see "feature" only. It will return a single feature. What I need is queryTask. developers.arcgis.com/en/javascript/jsapi/querytask.html which returns a featureset