MongoDB\Driver\Cursor::isDead

(mongodb >=1.0.0)

MongoDB\Driver\Cursor::isDeadChecks 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

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)