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ee.Dictionary.evaluate
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Recupera in modo asincrono il valore di questo oggetto dal server e lo passa alla funzione di callback fornita.
| Utilizzo | Resi |
|---|
Dictionary.evaluate(callback) | |
| Argomento | Tipo | Dettagli |
|---|
questo: computedobject | ComputedObject | L'istanza ComputedObject. |
callback | Funzione | Una funzione del modulo function(success, failure), chiamata quando il server restituisce una risposta. Se la richiesta è riuscita, l'argomento success contiene il risultato valutato. Se la richiesta non è riuscita, l'argomento failure conterrà un messaggio di errore. |
Esempi
Editor di codice (JavaScript)
// A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).
var dictServer = ee.Dictionary({
B1: 182,
B2: 219,
B3: 443
});
// Use evaluate to transfer server-side dictionary to the client.
dictServer.evaluate(function(dictClient) {
print('Client-side dot notation to access "B1" value', dictClient.B1);
print('Client-side bracket notation to access "B1" value', dictClient['B1']);
print('Client-side operations to print all key-value pairs');
Object.keys(dictClient).forEach(function(key) {
print(' ' + key + ': ' + dictClient[key]);
});
});
Configurazione di Python
Consulta la pagina
Ambiente Python per informazioni sull'API Python e sull'utilizzo di
geemap per lo sviluppo interattivo.
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.Dictionary objects.
# Use ee.Dictionary.getInfo() instead.
Salvo quando diversamente specificato, i contenuti di questa pagina sono concessi in base alla licenza Creative Commons Attribution 4.0, mentre gli esempi di codice sono concessi in base alla licenza Apache 2.0. Per ulteriori dettagli, consulta le norme del sito di Google Developers. Java è un marchio registrato di Oracle e/o delle sue consociate.
Ultimo aggiornamento 2025-07-26 UTC.
[null,null,["Ultimo aggiornamento 2025-07-26 UTC."],[[["\u003cp\u003e\u003ccode\u003eDictionary.evaluate()\u003c/code\u003e asynchronously retrieves the value of a server-side ComputedObject (like a dictionary) and passes it to a callback function.\u003c/p\u003e\n"],["\u003cp\u003eThe provided callback function handles the server response, receiving the evaluated result on success or an error message on failure.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eDictionary.evaluate()\u003c/code\u003e enables client-side access and manipulation of the server-side dictionary data using standard JavaScript operations.\u003c/p\u003e\n"],["\u003cp\u003eWhile the JavaScript API uses \u003ccode\u003eDictionary.evaluate()\u003c/code\u003e, the Python API leverages \u003ccode\u003eDictionary.getInfo()\u003c/code\u003e for synchronous retrieval of dictionary values.\u003c/p\u003e\n"]]],["The `evaluate` method asynchronously retrieves a `ComputedObject`'s value from the server and provides it to a callback function. The callback receives a success argument with the result or a failure argument with an error message. It's demonstrated with a dictionary example where server-side data is transferred to the client-side. In Python, `getInfo()` is used instead of `evaluate` for `ee.Dictionary` objects. The provided table details the usage, argument types, and their specifics.\n"],null,["# ee.Dictionary.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| Dictionary.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// A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).\nvar dictServer = ee.Dictionary({\n B1: 182,\n B2: 219,\n B3: 443\n});\n\n// Use evaluate to transfer server-side dictionary to the client.\ndictServer.evaluate(function(dictClient) {\n print('Client-side dot notation to access \"B1\" value', dictClient.B1);\n print('Client-side bracket notation to access \"B1\" value', dictClient['B1']);\n\n print('Client-side operations to print all key-value pairs');\n Object.keys(dictClient).forEach(function(key) {\n print(' ' + key + ': ' + dictClient[key]);\n });\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.Dictionary objects.\n# Use ee.Dictionary.getInfo() instead.\n```"]]
