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json_encode is returning NULL?
...e at least PHP 5.5, you can use json_last_error_msg(), which will return a string describing the problem.
If you don't have 5.5, but are on/above 5.3, you can use json_last_error() to see what the problem is.
It will return an integer, that you can use to identify the problem in the function's doc...
SQL SELECT WHERE field contains words
...
Note that if you use LIKE to determine if a string is a substring of another string, you must escape the pattern matching characters in your search string.
If your SQL dialect supports CHARINDEX, it's a lot easier to use it instead:
SELECT * FROM MyTable
WHERE CHARI...
What is the point of function pointers?
...orithm, but also data:
class functor {
public:
functor(const std::string& prompt) : prompt_(prompt) {}
void operator()(int i) {std::cout << prompt_ << i << '\n';}
private:
std::string prompt_;
};
functor f("the answer is: ");
f(42);
Another advantage is ...
How to construct a std::string from a std::vector?
Short of (the obvious) building a C style string first then using that to create a std::string, is there a quicker/alternative/"better" way to initialize a string from a vector of chars?
...
Why does struct alignment depend on whether a field type is primitive or user-defined?
...d750e0 000000e9 11111111 00000000 22222222 00000000
0xe90ed750e0 is the string pointer on my machine (not yours). You can easily see the Int32Wrappers, with the extra 4 bytes of padding that turned the size into 24 bytes. Go back to the struct and put the string last. Repeat and you'll see the...
List of standard lengths for database fields
...those were over 25, and they were all cases where data imports resulted in extra junk winding up in that field.)
Last name was similar to first name.
Email addresses maxed out at 62
characters. Most of the longer ones
were actually lists of email
addresses separated by semicolons.
Street address ma...
C++使用OLE/COM高速读写EXCEL的源码 - C/C++ - 清泛网 - 专注C/C++及内核技术
...l(BOOL bShow);
///检查一个CELL是否是字符串
//BOOL IsCellString(long iRow, long iColumn);
///检查一个CELL是否是数值
//BOOL IsCellInt(long iRow, long iColumn);
void SetCell(long irow, long icolumn,CString new_string);
///得到一个CELL的String
CString GetC...
PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
...t mb_detect_encoding source code in your php distro (somewhere here: ext/mbstring/libmbfl/mbfl/mbfl_ident.c). This function does not work properly at all. For some encodings it even has "return true", lol. Others are in Ctrl+c Ctrl+v functions. That's because you can not detect encoding without some...
Why does HTML5 form-validation allow emails without a dot?
...ould have a ^, denoting it should start matching from the beginning of the string and also accept upper case: ^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]+$
– Kohjah Breese
Dec 6 '18 at 14:18
...
How to get the value from the GET parameters?
...
JavaScript itself has nothing built in for handling query string parameters.
Code running in a (modern) browser you can use the URL object (which is part of the APIs provided by browsers to JS):
var url_string = "http://www.example.com/t.html?a=1&b=3&c=m2-m3-m4-m5"; /...