Laravel DB::transaction() 返回值
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原文地址: http://stackoverflow.com/questions/20176153/
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Laravel DB::transaction() return value
提问by enchance
It's my first time to use DB::transaction()but how exactly does it work if a transaction fails or is successful? In the example below, do I have to manually assign a value to return true, or if it fails will the method either return falseor totally exit the transaction (therefore skipping the rest of the code)? The docs aren't so helpful on this.
这是我第一次使用，DB::transaction()但如果交易失败或成功，它究竟是如何工作的？在下面的示例中，我是否必须手动为 return 分配一个值true，或者如果它失败，该方法将返回false还是完全退出事务（因此跳过其余代码）？文档对此没有太大帮助。
use Exception;
use DB;
try {
$success = DB::transaction(function() {
// Run some queries
});
print_r($success);
} catch(Exception $e) {
echo 'Uh oh.';
}
Solution
解决方案
I wrote down this solution for others who might be wondering.
我为其他可能想知道的人写下了这个解决方案。
Since I was more concerned about returning a boolean value depending on the success of my query, with a few modifications it now returns true/falsedepending on its success:
由于我更关心根据查询的成功返回一个布尔值，经过一些修改，它现在true/false根据查询的成功返回：
use Exception;
use DB;
try {
$exception = DB::transaction(function() {
// Run queries here
});
return is_null($exception) ? true : $exception;
} catch(Exception $e) {
return false;
}
Take note that the variable $exceptionis never returned since if something goes wrong with your query, the catchis immediately triggered returning false. Thanks to @ilaijin for showing that an Exceptionobject is thrown if something goes wrong.
请注意，该变量$exception永远不会返回，因为如果您的查询出现问题，将catch立即触发返回false. 感谢@ilaijin 展示了Exception如果出现问题会抛出一个对象。
采纳答案by ilpaijin
By giving a look at function transactionit does its process inside a try/catch block
通过查看function transaction它在 try/catch 块中执行的过程
public function transaction(Closure $callback)
{
$this->beginTransaction();
// We'll simply execute the given callback within a try / catch block
// and if we catch any exception we can rollback the transaction
// so that none of the changes are persisted to the database.
try
{
$result = $callback($this);
$this->commit();
}
// If we catch an exception, we will roll back so nothing gets messed
// up in the database. Then we'll re-throw the exception so it can
// be handled how the developer sees fit for their applications.
catch (\Exception $e)
{
$this->rollBack();
throw $e;
}
So throws an Exception (after the rollback) if fails or returns $result, which is the result of your callback
因此，如果失败或返回$result，则抛出异常（回滚后），这是回调的结果
回答by LeRoy
You can also use the following
您还可以使用以下
DB::rollback();
