大约有 6,000 项符合查询结果（耗时：0.0253秒） [XML]
PHP regular expressions: No ending delimiter '^' found in
...
PHP regex strings need delimiters. Try:
$numpattern="/^([0-9]+)$/";
Also, note that you have a lower case o, not a zero. In addition, if you're just validating, you don't need the capturing group, and can simplify the rege...
Does the Java &= operator apply & or &&?
...So a &= b; is equivalent to a = a & b;.
(In some usages, the type-casting makes a difference to the result, but in this one b has to be boolean and the type-cast does nothing.)
And, for the record, a &&= b; is not valid Java. There is no &&= operator.
In practice, there...
How do I check if a SQL Server text column is empty?
...he added overhead of calling SQL Functions like DataLength(), IsNull(), or Cast(). Maybe the generated query plan is the same (I didn't check); still I find this to be a far cleaner approach.
– MikeTeeVee
Nov 13 '19 at 11:49
...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...
Whenever using "%p" on printf, you should cast the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44...
What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...st() along the way.
What do these methods do?
AsEnumerable and AsQueryable cast or convert to IEnumerable or IQueryable, respectively. I say cast or convert with a reason:
When the source object already implements the target interface, the source object itself is returned but cast to the target int...
PHP variables in anonymous functions
I was playing around with anonymous functions in PHP and realized that they don't seem to reach variables outside of them.
Is there any way to get around this problem?
...
How do I create a comma-separated list from an array in PHP?
...ut it's always a pain having to take off the final comma. Is there an easy PHP way of doing it?
12 Answers
...
How to convert an image to base64 encoding?
...ts("/path/to/image.jpg");
// alternatively specify an URL, if PHP settings allow
$base64 = base64_encode($imagedata);
bear in mind that this will enlarge the data by 33%, and you'll have problems with files whose size exceed your memory_limit.
...
Reset PHP Array Index
I have a PHP array that looks like this:
3 Answers
3
...
How to make PDF file downloadable in HTML link?
...nking to the .PDF file, instead do something like
<a href="pdf_server.php?file=pdffilename">Download my eBook</a>
which outputs a custom header, opens the PDF (binary safe) and prints the data to the user's browser, then they can choose to save the PDF despite their browser settings....