大约有 43,000 项符合查询结果(耗时:0.0261秒) [XML]
How to easily map c++ enums to strings
...mes themselves as strings, see this post.
Otherwise, a std::map<MyEnum, char const*> will work nicely. (No point in copying your string literals to std::strings in the map)
For extra syntactic sugar, here's how to write a map_init class. The goal is to allow
std::map<MyEnum, const char*&g...
typedef fixed length array
I have to define a 24-bit data type.I am using char[3] to represent the type. Can I typedef char[3] to type24 ? I tried it in a code sample. I put typedef char[3] type24; in my header file. The compiler did not complain about it. But when I defined a function void foo(type24 val) {} in my C...
C语言结构体里的成员数组和指针 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
16
17
#include <stdio.h>
struct str{
int len;
char s[0];
};
struct foo {
struct str *a;
};
int main(int argc, char** argv) {
struct foo f={0};
if (f.a->s) {
printf( f.a->s);
}
return 0;
}
你编...
Get the new record primary key ID from MySQL insert query?
...
Eg:
INSERT INTO table_name (col1, col2,...) VALUES ('val1', 'val2'...);
SELECT LAST_INSERT_ID();
This will get you back the PRIMARY KEY value of the last row that you inserted:
The ID that was generated is maintained in the server on a per-connection basis. This means that the value returne...
Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'?,./
...al letters represent the negation of their lowercase counterparts.
\W will select all non "word" characters equivalent to [^a-zA-Z0-9_]
\S will select all non "whitespace" characters equivalent to [ \t\n\r\f\v]
_ will select "_" because we negate it when using the \W and need to add it back in
...
What's the rationale for null terminated strings?
...
From the horse's mouth
None of BCPL, B, or C supports
character data strongly in the
language; each treats strings much
like vectors of integers and
supplements general rules by a few
conventions. In both BCPL and B a
string literal denotes the address of
a static ar...
Replace a character at a specific index in a string?
I'm trying to replace a character at a specific index in a string.
8 Answers
8
...
Why use double indirection? or Why use pointers to pointers?
...
If you want to have a list of characters (a word), you can use char *word
If you want a list of words (a sentence), you can use char **sentence
If you want a list of sentences (a monologue), you can use char ***monologue
If you want a list of monologue...
“#include” a text file in a C program as a char[]
... use it like so
$ echo hello world > a
$ xxd -i a
outputs:
unsigned char a[] = {
0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x77, 0x6f, 0x72, 0x6c, 0x64, 0x0a
};
unsigned int a_len = 12;
share
|
...
PreparedStatement IN clause alternatives?
... and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_...