更新包含数组字段的 Firestore 文档

更新包含数组字段的 Firestore 文档。

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如需查看包含此代码示例的详细文档，请参阅以下内容：

代码示例

C#

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

DocumentReference washingtonRef = db.Collection("cities").Document("DC");

// Atomically add a new region to the "regions" array field.
await washingtonRef.UpdateAsync("Regions", FieldValue.ArrayUnion("greater_virginia"));

// Atomically remove a region from the "regions" array field.
await washingtonRef.UpdateAsync("Regions", FieldValue.ArrayRemove("east_coast"));

Java

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

DocumentReference washingtonRef = db.collection("cities").document("DC");

// Atomically add a new region to the "regions" array field.
ApiFuture<WriteResult> arrayUnion =
    washingtonRef.update("regions", FieldValue.arrayUnion("greater_virginia"));
System.out.println("Update time : " + arrayUnion.get());

// Atomically remove a region from the "regions" array field.
ApiFuture<WriteResult> arrayRm =
    washingtonRef.update("regions", FieldValue.arrayRemove("east_coast"));
System.out.println("Update time : " + arrayRm.get());

Node.js

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

// ...
const washingtonRef = db.collection('cities').doc('DC');

// Atomically add a new region to the "regions" array field.
const unionRes = await washingtonRef.update({
  regions: FieldValue.arrayUnion('greater_virginia')
});
// Atomically remove a region from the "regions" array field.
const removeRes = await washingtonRef.update({
  regions: FieldValue.arrayRemove('east_coast')
});

// To add or remove multiple items, pass multiple arguments to arrayUnion/arrayRemove
const multipleUnionRes = await washingtonRef.update({
  regions: FieldValue.arrayUnion('south_carolina', 'texas')
  // Alternatively, you can use spread operator in ES6 syntax
  // const newRegions = ['south_carolina', 'texas']
  // regions: FieldValue.arrayUnion(...newRegions)
});

PHP

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

$cityRef = $db->collection('samples/php/cities')->document('DC');

// Atomically add a new region to the "regions" array field.
$cityRef->update([
    ['path' => 'regions', 'value' => FieldValue::arrayUnion(['greater_virginia'])]
]);

// Atomically remove a region from the "regions" array field.
$cityRef->update([
    ['path' => 'regions', 'value' => FieldValue::arrayRemove(['east_coast'])]
]);

Python

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

city_ref = db.collection("cities").document("DC")

# Atomically add a new region to the 'regions' array field.
city_ref.update({"regions": firestore.ArrayUnion(["greater_virginia"])})

# // Atomically remove a region from the 'regions' array field.
city_ref.update({"regions": firestore.ArrayRemove(["east_coast"])})

Ruby

如需向 Firestore 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为本地开发环境设置身份验证。 

city_ref = firestore.doc "#{collection_path}/DC"

# Atomically add a new region to the 'regions' array field.
city_ref.update({ regions: firestore.field_array_union("greater_virginia") })

# Atomically remove a region from the 'regions' array field.
city_ref.update({ regions: firestore.field_array_delete("east_coast") })

后续步骤

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