ee.FeatureCollection.evaluate
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Asynchronicznie pobiera wartość tego obiektu z serwera i przekazuje ją do podanej funkcji wywołania zwrotnego.
| Wykorzystanie | Zwroty |
|---|
FeatureCollection.evaluate(callback) | |
| Argument | Typ | Szczegóły |
|---|
to: computedobject | ComputedObject | Instancja ComputedObject. |
callback | Funkcja | Funkcja w formacie function(success, failure), wywoływana, gdy serwer zwraca odpowiedź. Jeśli żądanie się powiodło, argument success zawiera oceniony wynik. Jeśli żądanie się nie powiedzie, argument failure będzie zawierać komunikat o błędzie. |
Przykłady
Edytor kodu (JavaScript)
/**
* WARNING: this function transfers data from Earth Engine servers to the
* client. Doing so can negatively affect request processing and client
* performance. Server-side options should be used whenever possible.
* Learn more about the distinction between server and client:
* https://developers.google.com/earth-engine/guides/client_server
*/
// FeatureCollection of power plants in Belgium.
var fcServer = ee.FeatureCollection('WRI/GPPD/power_plants')
.filter('country_lg == "Belgium"');
fcServer.evaluate(function(fcClient) {
print('Client-side feature collection is an object', typeof fcClient);
print('Feature collection object keys', Object.keys(fcClient));
print('Array of features', fcClient.features);
print('Properties for first feature', fcClient.features[0].properties);
});
Konfiguracja Pythona
Informacje o interfejsie Python API i używaniu geemap do interaktywnego programowania znajdziesz na stronie
Środowisko Python.
import ee
import geemap.core as geemap
Colab (Python)
# The Earth Engine Python client library does not have an evaluate method for
# asynchronous evaluation of ee.FeatureCollection objects.
# Use ee.FeatureCollection.getInfo() instead.
O ile nie stwierdzono inaczej, treść tej strony jest objęta licencją Creative Commons – uznanie autorstwa 4.0, a fragmenty kodu są dostępne na licencji Apache 2.0. Szczegółowe informacje na ten temat zawierają zasady dotyczące witryny Google Developers. Java jest zastrzeżonym znakiem towarowym firmy Oracle i jej podmiotów stowarzyszonych.
Ostatnia aktualizacja: 2025-07-26 UTC.
[null,null,["Ostatnia aktualizacja: 2025-07-26 UTC."],[[["\u003cp\u003e\u003ccode\u003eevaluate()\u003c/code\u003e retrieves the value of a ComputedObject (like a FeatureCollection) from the Earth Engine server and passes it to a callback function.\u003c/p\u003e\n"],["\u003cp\u003eThe callback function is structured as \u003ccode\u003efunction(success, failure)\u003c/code\u003e where \u003ccode\u003esuccess\u003c/code\u003e contains the result if the request succeeds, and \u003ccode\u003efailure\u003c/code\u003e contains an error message if it fails.\u003c/p\u003e\n"],["\u003cp\u003eThis method transfers data from the server to the client, potentially impacting performance; server-side options are generally preferred.\u003c/p\u003e\n"],["\u003cp\u003eFor asynchronous evaluation of \u003ccode\u003eee.FeatureCollection\u003c/code\u003e in the Earth Engine Python client library, use \u003ccode\u003egetInfo()\u003c/code\u003e instead of \u003ccode\u003eevaluate()\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,["# ee.FeatureCollection.evaluate\n\n\u003cbr /\u003e\n\nAsynchronously retrieves the value of this object from the server and passes it to the provided callback function.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|----------------------------------------|---------|\n| FeatureCollection.evaluate`(callback)` | |\n\n| Argument | Type | Details |\n|------------------------|----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `computedobject` | ComputedObject | The ComputedObject instance. |\n| `callback` | Function | A function of the form function(success, failure), called when the server returns an answer. If the request succeeded, the success argument contains the evaluated result. If the request failed, the failure argument will contains an error message. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n/**\n * WARNING: this function transfers data from Earth Engine servers to the\n * client. Doing so can negatively affect request processing and client\n * performance. Server-side options should be used whenever possible.\n * Learn more about the distinction between server and client:\n * https://developers.google.com/earth-engine/guides/client_server\n */\n\n// FeatureCollection of power plants in Belgium.\nvar fcServer = ee.FeatureCollection('WRI/GPPD/power_plants')\n .filter('country_lg == \"Belgium\"');\n\nfcServer.evaluate(function(fcClient) {\n print('Client-side feature collection is an object', typeof fcClient);\n print('Feature collection object keys', Object.keys(fcClient));\n print('Array of features', fcClient.features);\n print('Properties for first feature', fcClient.features[0].properties);\n});\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# The Earth Engine Python client library does not have an evaluate method for\n# asynchronous evaluation of ee.FeatureCollection objects.\n# Use ee.FeatureCollection.getInfo() instead.\n```"]]
