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Why do we need C Unions?
... Here is a trivial example:
typedef union
{
struct {
unsigned char byte1;
unsigned char byte2;
unsigned char byte3;
unsigned char byte4;
} bytes;
unsigned int dword;
} HW_Register;
HW_Register reg;
Then you can access the reg as follows:
reg.dword = 0x...
How to remove all line breaks from a string
...match all variants is
/\r?\n|\r/
If you want to match all newlines in a string, use a global match,
/\r?\n|\r/g
respectively. Then proceed with the replace method as suggested in several other answers. (Probably you do not want to remove the newlines, but replace them with other whitespace, f...
Difference: std::runtime_error vs std::exception()
...
std::runtime_error on the other hand has valid constructors that accept a string as a message. When what() is called a const char pointer is returned that points at a C string that has the same string as was passed into the constructor.
try
{
if (badThingHappened)
{
throw std::run...
The entity type is not part of the model for the current context
...have a number of reasons. In my case, it was the following: The connection string (in Web.config) generated by the .edmx was invalid. After almost a day of trying everything, I changed the connection string from the EF string to an ADO.NET string. This solved my issue.
For example, the EF string lo...
sizeof single struct member in C
...->member)
and use it like this:
typedef struct
{
float calc;
char text[255];
int used;
} Parent;
typedef struct
{
char flag;
char text[member_size(Parent, text)];
int used;
} Child;
I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a ...
Semicolon before self-invoking function? [duplicate]
...: there isn't one! (Learn only one rule and you too can enjoy life without extra semicolons ;-)
Since I write in a semicolon-free style I thus always write it as (where the function-expression can naturally span multiple lines):
;(FunctionExpression)()
In my case it isn't about "safety" or try...
Identify if a string is a number
If I have these strings:
25 Answers
25
...
Use email address as primary key?
...
String comparison is slower than int comparison. However, this does not matter if you simply retrieve a user from the database using the e-mail address. It does matter if you have complex queries with multiple joins.
If you ...
What is the email subject length limit?
...56 is any better than 250, or 300, or 372. We're long past using bytes for string lengths.
– Greg Hewgill
Oct 20 '09 at 3:46
4
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How to send emails from my Android application?
...N_SEND);
i.setType("message/rfc822");
i.putExtra(Intent.EXTRA_EMAIL , new String[]{"recipient@example.com"});
i.putExtra(Intent.EXTRA_SUBJECT, "subject of email");
i.putExtra(Intent.EXTRA_TEXT , "body of email");
try {
startActivity(Intent.createChooser(i, "Send mail..."));
} catch (android.c...