php 为什么 DateTime::createFromFormat() 在我的第二个示例中失败并返回一个布尔值？
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Why does DateTime::createFromFormat() fails and returns a boolean in my second example?
提问by depperm
When I run this the first one is correctly created into a date. The second one fails, returning a booleanand so I cannot format. Is the time out of range?
当我运行它时，第一个被正确创建为日期。第二个失败，返回一个boolean，所以我无法格式化。时间是否超出范围？
//works correctly
$startDate = "2015-05-06 10:49:20.637133";
$start = DateTime::createFromFormat('Y-m-d h:m:s.u',$startDate);
echo $start->format('m/d/y');
//doesn't work correctly
$startDate = "2015-05-12 15:49:06.821289";
$start = DateTime::createFromFormat('Y-m-d h:m:s.u',$startDate);
echo $start->format('m/d/y');
采纳答案by Rizier123
Change the hto a big H, since the small one is 12-hours format and the big one is 24-hours format.
将 更改h为大H，因为小是 12 小时格式，大是 24 小时格式。
You can see all formats in the manual. And a quote from there:
您可以在手册中看到所有格式。和那里的报价：
h 12-hour formatof an hour with leading zeros 01 through 12
H 24-hour formatof an hour with leading zeros 00 through 23
h带有前导零 01 到 12
的小时的12小时格式 H带有前导零 00 到 23 的小时的24 小时格式
Means right now your code fails, because there is no 15 in the 12 hour format.
意味着现在您的代码失败了，因为 12 小时格式中没有 15。
回答by Marc B
Check DateTime::getLastErrors():
检查DateTime::getLastErrors()：
php > var_dump(DateTime::createFromFormat('Y-m-d h:m:s',"2015-05-12 15:49:06"));
bool(false)
php > var_dump(DateTime::getLastErrors());
array(4) {
["warning_count"]=>
int(1)
["warnings"]=>
array(1) {
[19]=>
string(27) "The parsed date was invalid"
}
["error_count"]=>
int(1)
["errors"]=>
array(1) {
[11]=>
string(30) "Hour can not be higher than 12"
回答by AbraCadaver
In addition to the other answers, for standard formats understood by DateTimeyou don't need to create from a format:
除了其他答案之外，对于DateTime您理解的标准格式，您不需要从格式创建：
$startDate = "2015-05-12 15:49:06.821289";
$start = new DateTime($startDate);
echo $start->format('m/d/y');
