大约有 45,000 项符合查询结果(耗时:0.0349秒) [XML]

https://stackoverflow.com/ques... 

Why isn't vector a STL container?

...l directly. Workarounds to avoid this range from using a different type (char, unsigned char) or container (like deque) to use wrapper types or further specialize for specific allocator types. bitset is a class that provides a similar functionality for fixed-size arrays of bits. ...
https://stackoverflow.com/ques... 

When would anyone use a union? Is it a remnant from the C-only days?

...own Variant type: struct my_variant_t { int type; union { char char_value; short short_value; int int_value; long long_value; float float_value; double double_value; void* ptr_value; }; }; Then you would use it such as: /* const...
https://stackoverflow.com/ques... 

How to TryParse for Enum value?

... = Enum.ToObject(type, ul); return true; } private static char[] _enumSeperators = new char[] { ',', ';', '+', '|', ' ' }; private static object EnumToObject(Type underlyingType, string input) { if (underlyingType == typeof(int)) { int s; ...
https://stackoverflow.com/ques... 

How do you use the “WITH” clause in MySQL?

...s mentioned, you provided a poor example - there's no need to perform a subselect if you aren't altering the output of the columns in any way: SELECT * FROM ARTICLE t JOIN USERINFO ui ON ui.user_userid = t.article_ownerid JOIN CATEGORY c ON c.catid = t.article_categoryid WHERE t....
https://stackoverflow.com/ques... 

Best way to select random rows PostgreSQL

I want a random selection of rows in PostgreSQL, I tried this: 12 Answers 12 ...
https://stackoverflow.com/ques... 

MySQL INNER JOIN select only one row from second table

...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help ...
https://stackoverflow.com/ques... 

Is a Java string really immutable?

.... However, looking at the source code of String, we can see that the value character array for a substring is actually copied (using Arrays.copyOfRange(..)). This is why it goes unchanged. You can install a SecurityManager, to avoid malicious code to do such things. But keep in mind that some libra...
https://stackoverflow.com/ques... 

Get selected value/text from Select on change

I need to get the value of the selected option in javascript: does anyone know how to get the selected value or text, please tell how to write a function for it. I have assigned onchange() function to select so what do i do after that? ...
https://stackoverflow.com/ques... 

Why is C so fast, and why aren't other languages as fast or faster? [closed]

...what the machine does can be seen in the rules that govern the widening of char objects for use in expressions: whether the values of char objects widen to signed or unsigned quantities typically depends on which byte operation is more efficient on the target machine. ...
https://stackoverflow.com/ques... 

How to get cumulative sum

the above select returns me the following. 16 Answers 16 ...