MongoDB\Driver\Cursor::isDead

(mongodb >=1.0.0)

MongoDB\Driver\Cursor::isDead — Checks if the cursor may have additional results

说明

final public MongoDB\Driver\Cursor::isDead ( void ) : bool

Checks whether the cursor may have additional results available to read. A cursor is initially "alive" but may become "dead" for any of the following reasons:

Advancing a non-tailable cursor did not return a document
The cursor encountered an error
The cursor read its last batch to completion
The cursor reached its configured limit

This is primarily useful with tailable cursors.

参数

此函数没有参数。

返回值

Returns TRUE if additional results are not available, and FALSE otherwise.

错误／异常

Throws MongoDB\Driver\Exception\InvalidArgumentException on argument parsing errors.

范例

Example #1 MongoDB\Driver\Cursor::isDead() example


<?php

$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");
$query = new MongoDB\Driver\Query([]);

$bulk = new MongoDB\Driver\BulkWrite;
$bulk->insert(['x' => 1]);
$bulk->insert(['x' => 2]);
$bulk->insert(['x' => 3]);
$manager->executeBulkWrite('db.collection', $bulk);

$cursor = $manager->executeQuery('db.collection', $query);

$iterator = new IteratorIterator($cursor);

$iterator->rewind();
var_dump($cursor->isDead());

$iterator->next();
var_dump($cursor->isDead());

$iterator->next();
var_dump($cursor->isDead());

$iterator->next();
var_dump($cursor->isDead());

?>

以上例程会输出：

bool(false)
bool(false)
bool(false)
bool(true)