ee.Date.evaluate

從伺服器非同步擷取這個物件的值，並傳遞至提供的回呼函式。

用量	傳回
Date.evaluate(callback)

引數	類型	詳細資料
這個：computedobject	ComputedObject	ComputedObject 例項。
callback	函式	伺服器傳回答案時呼叫的函式，格式為 function(success, failure)。如果要求成功，success 引數會包含評估結果。如果要求失敗，失敗引數會包含錯誤訊息。

範例

程式碼編輯器 (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
 */

// A server-side ee.Date object.
var dateServer = ee.Date('2021-4-30');

// Use evaluate to transfer server-side date to the client. The result is
// an object with keys "type" and "value" where "value" is milliseconds since
// Unix epoch.
dateServer.evaluate(function(dateClient) {
  print('Client-side date is an object', typeof dateClient);
  print('Object keys include "type" and "value"', Object.keys(dateClient));
  print('"value" is milliseconds since Unix epoch', dateClient.value);
  print('Client-side date in JS Date constructor', new Date(dateClient.value));
});

Python 設定

請參閱 Python 環境頁面，瞭解 Python API 和如何使用 geemap 進行互動式開發。

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.Date objects.
# Use ee.Date.getInfo() instead.