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Importance of varchar length in MySQL table
...s are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
...
Why .NET String is immutable? [duplicate]
As we all know, String is immutable. What are the reasons for String being immutable and the introduction of StringBuilder class as mutable?
...
C/C++ line number
...andard. During preprocessing, they are replaced respectively by a constant string holding an integer representing the current line number and by the current file name.
Others preprocessor variables :
__func__ : function name (this is part of C99, not all C++ compilers support it)
__DATE__ : a str...
Why is iostream::eof inside a loop condition (i.e. `while (!stream.eof())`) considered wrong?
... out that this answer is slightly misleading. When extracting ints or std::strings or similar, the EOF bit is set when you extract the one right before the end and the extraction hits the end. You do not need to read again. The reason it doesn't get set when reading from files is because there's an ...
Print text instead of value from C enum
...in C are numbers that have convenient names inside your code. They are not strings, and the names assigned to them in the source code are not compiled into your program, and so they are not accessible at runtime.
The only way to get what you want is to write a function yourself that translates the ...
How do I convert between big-endian and little-endian values in C++?
...nsigned __int64 _byteswap_uint64(unsigned __int64 value);
8 bit numbers (chars) don't need to be converted.
Also these are only defined for unsigned values they work for signed integers as well.
For floats and doubles it's more difficult as with plain integers as these may or not may be in the h...
What belongs in an educational tool to demonstrate the unwarranted assumptions people make in C/C++?
...lo"); /* printf() returns the number of
characters successfully printed by it
*/
}
int World()
{
return printf("World !");
}
int main()
{
int a = Hello() + World(); //might print Hello World! or World! Hell...
How can I limit possible inputs in a HTML5 “number” element?
...-numeric characters to be entered, because object.length would be an empty string for the number inputs, and therefore its length would be 0. Thus the maxLengthCheck function won't work.
Solution:
See this or this for examples.
Demo - See the full version of the code here:
http://jsfiddle.net/DRSD...
浅析为什么char类型的范围是 -128~+127 - C/C++ - 清泛网 - 专注C/C++及内核技术
浅析为什么char类型的范围是 -128~+127在C语言中， signed char 类型的范围为-128~127,每本教科书上也这么写，但是没有哪一本书上（包括老师）也不会给你为什么是-128~127，这...在C语言中， signed char 类型的范围为-128~127,每本教科书上...
Immutability of Strings in Java
...bject, it's a reference to an object. "Hello" and "Help!" are two distinct String objects. Thus, str points to a string. You can change what it points to, but not that which it points at.
Take this code, for example:
String s1 = "Hello";
String s2 = s1;
// s1 and s2 now point at the same string - "H...