大约有 44,000 项符合查询结果（耗时：0.0349秒） [XML]
How to check for a valid Base64 encoded string
...s pretty easy to recognize a Base64 string, as it will only be composed of characters 'A'..'Z', 'a'..'z', '0'..'9', '+', '/' and it is often padded at the end with up to three '=', to make the length a multiple of 4. But instead of comparing these, you'd be better off ignoring the exception, if it o...
How do you compare structs for equality in C?
...use memcmp to compare structs for equality due to potential random padding characters between field in structs.
// bad
memcmp(&struct1, &struct2, sizeof(struct1));
The above would fail for a struct like this:
typedef struct Foo {
char a;
/* padding */
double d;
/* padding */
...
Stop Excel from automatically converting certain text values to dates
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In my MySQL query (for CSV output through PHP), I used CONCAT('\t', column_name). Also did the trick. Thanks!
– Just Plain High
Jun 24 '16 at 14:39
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When would I need a SecureString in .NET?
...dance from MS is: SecureString shouldn't be used
– Richard Morgan
Jul 5 '19 at 11:24
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Getting a File's MD5 Checksum in Java
... byte data[] = org.apache.commons.codec.digest.DigestUtils.md5(fis); char md5Chars[] = Hex.encodeHex(data); String md5 = String.valueOf(md5Chars);`
– Dmitry_L
Jul 17 '13 at 10:45
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C++ equivalent of StringBuffer/StringBuilder?
...As far as I know std::string cannot simply extend the size of its internal char*. That means mutating it in a way which requires more characters requires a reallocation and copying. It's no different than a vector of chars and it is certainly better to reserve the space you need in that case.
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Convert pandas dataframe to NumPy array
...early the same (actually, using rec.fromrecords is a bit faster).
df2 = pd.concat([df] * 10000)
%timeit df2.to_records()
%%timeit
v = df2.reset_index()
np.rec.fromrecords(v, names=v.columns.tolist())
11.1 ms ± 557 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
9.67 ms ± 126 µs per l...
How to read from a file or STDIN in Bash?
...ter to add -r to your read command, so that it doesn't accidentally eat \ chars; use while IFS= read -r line to preserve leading and trailing whitespace.
– mklement0
Feb 28 '15 at 23:34
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generating GUID without hyphen
... is it possible to create a GUID with both Upper and lowercase chars along with numbers???
– Harish Kumar
Jan 16 '12 at 8:55
7
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Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...or is expected to for decades. The prime example is compiling X11, macro "Concat3" is broken, it's result is now MISNAMED C Identifier, which of course fails to build. and i'm beginning to thing build fails are their profession.
I think the answer here is "new C that breaks standards is bad C", t...