Search Results

Search found 7500 results on 300 pages for 'const char'.

Page 230/300 | < Previous Page | 226 227 228 229 230 231 232 233 234 235 236 237  | Next Page >

• How does make_pair know the types of its args?

  - by bobobobo

  The definition for make_pair in the MSVC++ "utility" header is: template<class _Ty1, class _Ty2> inline pair<_Ty1, _Ty2> make_pair(_Ty1 _Val1, _Ty2 _Val2) { // return pair composed from arguments return (pair<_Ty1, _Ty2>(_Val1, _Val2)); } I use make_pair all the time though without putting the argument types in angle brackets: map<string,int> theMap ; theMap.insert( make_pair( "string", 5 ) ) ; Shouldn't I have to tell make_pair that the first argument is std::string and not char* ? How does it know?

  Read the article

• Why does the Win32-API have so many custom types?

  - by sub

  I'm new to the Win32 API and the many new types begin to confuse me. Some functions take 1-2 ints and 3 UINTS as arguments. Why can't they just use ints? What are UINTS? Then, there are those other types: DWORD LPCWSTR LPBOOL Again, I think the "primitive" C types would be enough - why introduce 100 new types? This one was a pain: WCHAR* I had to iterate through it and push_back every character to an std::string as there wasn't another way to convert it to one. Horrible. Why WCHAR? Why reinvent the wheel? They could have just used char* instead, or?

  Read the article

• Obtain container type from (its) iterator type in C++ (STL)

  - by KRao

  It is easy given a container to get the associated iterators, example: std::vector<double>::iterator i; //An iterator to a std::vector<double> I was wondering if it is possible, given an iterator type, to deduce the type of the "corresponding container" (here I am assuming that for each container there is one and only one (non-const) iterator). More precisely, I would like a template metafunction that works with all STL containers (without having to specialize it manually for each single container) such that, for example: ContainerOf< std::vector<double>::iterator >::type evaluates to std::vector<double> Is it possible? If not, why? Thank you in advance for any help!

  Read the article

• When should we use * and & and . and -> ?

  - by uzay95

  Why we are using * character when we are creating button but we aren't adding it to app instance? #include <QApplication> #include <QPushButton> int main(int argc,char *argv[]) { QApplication app(argc,argv); QPushButton *button = new QPushButton("Button Text"); QObject::connect(button,SIGNAL(clicked()),&app,SLOT(quit())); button->show(); return app.exec(); } When should we use * and & and . and - ?

  Read the article

• creating new array according to input

  - by gcc

  int *arrays[20],j,a=0; /*int num_arrays;*/ char *tutar[200]; int /*fe*/i=0,n,temp; do{ tutar[i]=malloc(sizeof(int)); scanf("%s",tutar[i]); temp=*tutar[i]; ++i; } while(temp!='x'); int *arrays[20],j,a=0; n=i; j=1; for(i=1;i if(atoi(tutar[i])=='n') { ++j; arrays[j]=malloc(sizeof(int)); a=0; } arrays[j][a]=*(int *)tutar[i]; if(atoi(tutar[i])=='x') break; } input: 1 2 3 4 n 14 23 39 n 98 100 x output: arrays[1]:2 3 4 arrays[2]:14 23 39 arrays[3]:98 100 //i wanna output like that but my code didnt give me output like that //can anyone fix my code or (explain where is my error)

  Read the article

• How to cin Space in c++?

  - by Narek

  Say we have a code: int main() { char a[10]; for(int i = 0; i < 10; i++) { cin>>a[i]; if(a[i] = ' ') cout<<"It is a space!!!"<<<endl; } return 0; } How to cin a Space symbol from command line? If you write space, program ignores! :(

  Read the article

• freeing malloc and checkin it is empty or not

  - by gcc

  char *p; p="kjkjk"; . .//there are codes which are checking another command . if(.....)//i used pointer p in only that area free(p); . . //there are codes which are checking another command . if(p==NULL) //i check whether is empty .... if(p==-1) //can we use "EOF==p " in if statement ... //are there any usage like that EOF==p else .... I think there is big error , but where?

  Read the article

• Need help making this code more efficient

  - by Rendicahya

  I always use this method to easily read the content of a file. Is it efficient enough? Is 1024 good for the buffer size? public static String read(File file) { FileInputStream stream = null; StringBuilder str = new StringBuilder(); try { stream = new FileInputStream(file); } catch (FileNotFoundException e) { } FileChannel channel = stream.getChannel(); ByteBuffer buffer = ByteBuffer.allocate(1024); try { while (channel.read(buffer) != -1) { buffer.flip(); while (buffer.hasRemaining()) { str.append((char) buffer.get()); } buffer.rewind(); } } catch (IOException e) { } finally { try { channel.close(); stream.close(); } catch (IOException e) { } } return str.toString(); }

  Read the article

• debug assertion fail

  - by Kolt

  I have a program that runs correctly if I start it manually. However, if I try to add a registry key to start it automatically during startup, I get this error: Debug assertion failed (str!=null) fprintf.c line:55 I tried to add Sleep(20000) before anything hapens, but same error. here`s the code: main() { FILE* filetowrite; filetowrite = fopen("textfile.txt", "a+"); writefunction(filetowrite); } int writefunction(FILE* filetowrite) { fprintf(filetowrite, "%s", "\n\n"); ... } I also tried with passing filename as char* and opening it in wrtiefunction(), but same error.

  Read the article

• what is the reason i am getting out put is 111?

  - by kam

  Hi, #include "stdafx.h" #include<iostream.h> template<class T> class Sample { public: Sample(); static int i; }; template<class T> int Sample<T>::i = 0; template<class T> Sample<T>::Sample() { i++; cout<<i; } void main() { Sample<int>s1; Sample<float>s2; Sample<char>s3; } output: 111 what is the reason i am getting out put is 111?

  Read the article

• Why can't i call Contains method from my array?

  - by xbnevan

  Arrrg!I am running into what i feel is a dumb issue with a simple script i'm writing in powershell. I am invoking a sql command that is calling a stored proc, with the results i put it a array. The results look something like this: Status ProcessStartTime ProcessEndTime ------ ---------------- -------------- Expired May 22 2010 8:31PM May 22 2010 8:32PM What i'm trying to do is if($s.Contains("Expired")) , report failed. Simple...? :( Problem i'm running into is it looks like Contains method is not being loaded as i get an error like this: Method invocation failed because [System.Object[]] doesn't contain a method named 'Contains'. At line:1 char:12 + $s.Contains <<<< ("Expired") + CategoryInfo : InvalidOperation: (Contains:String) [], RuntimeException + FullyQualifiedErrorId : MethodNotFound So, what can i do to stop powershell from unrolling it to string? Actual ps script below - $s = @(Invoke-Sqlcmd -Query "USE DB GO exec Monitor_TEST_ps 'EXPORT_RUN',NULL,20 " ` -ServerInstance "testdb002\testdb_002") if ($s.Contains("Expired")) { Write-Host "Expired found, FAIL." } else { Write-Host "Not found, OK." }

  Read the article

• an error within context

  - by helloWorld

  can somebody please explain my mistake, I have this class: class Account{ private: string strLastName; string strFirstName; int nID; int nLines; double lastBill; public: Account(string firstName, string lastName, int id); friend string printAccount(string firstName, string lastName, int id, int lines, double lastBill); } but when I call it: string reportAccounts() const { string report(printAccountsHeader()); for(list<Account>::const_iterator i = listOfAccounts.begin(); i != listOfAccounts.end(); ++i){ report += printAccount(i->strFirstName, i->strLastName, i->nID, i->nLines, i->lastBill);; } return report; } I receive error within context, can somebody explain why? thanks in advance

  Read the article

• Question about r-value in C++0x

  - by Goofy

  Rvalues IMHO are great improvement in C++, but at the beginning the're seems quite. Please look at code below: #include <string> std::string && foo (void) { std::string message ("Hello!"); return std::move (message); } void bar (const std::string &message2) { if (message == "Bye Bye!") return; } int main () { bar (foo ()); } Reference message2 is last owner of original message object returned by foo(), right?

  Read the article

• lambda+for_each+delete on STL containers

  - by rubenvb

  I'm trying to get a simple delete every pointer in my vector/list/... function written with an ultra cool lambda function. Mind you, I don't know c**p about those things :) template <typename T> void delete_clear(T const& cont) { for_each(T.begin(), T.end(), [](???){ ???->delete() } ); T.clear(); } I have no clue what to fill in for the ???'s. Any help is greatly appreciated!

  Read the article

• GWT : Composite not displaying

  - by animatrix30

  I have a this code for the layout : grid = new Grid(15, 15); tiles = new Tile[15][15]; for (int i = 0; i != 15; i++) { for (int j = 0; j != 15; j++) { tiles[i][j] = new Tile('a'); grid.setWidget(i, j, tiles[i][j]); tiles[i][j].setVisible(true); } } initWidget(grid); I know it is working, because if I change the tile, by a Button, it works well. Now my Tile class : public class Tile extends Composite { char character; public Tile (Character c) { this.character = c; buildWidget(); } private void buildWidget() { Label l = new Label(this.character+""); initWidget(l); } Why does all tiles are not displayed ? Thanks for your help !

  Read the article

• c language:make fgets to keep taking input until I press enter twice?

  - by wello horld

  hi I would like to ask how I would modify this code for the question: (It only accepts one input then prints it out. I want it to keep going until I hit enter (\n) twice. #include <stdio.h> #define MAXLENGTH 1000 int main(void) { char string[MAXLENGTH]; fgets(string, MAXLENGTH, stdin ); printf("%s\n", string); return 0; } I'm confused at the fgets(string, MAXLENGTH, stdin ); line, what does stdin mean/do?

  Read the article

• An array of structures in C...

  - by 00010000

  For the life of me I can't figure out the proper syntax for creating an array of structures in C. I tried this: struct foo { int x; int y; } foo[][] = { { { 1, 2 }, { 4, 5 }, { -1, -1 } }, { { 55, 44 } { 100, 200 }, } }; So for example foo[1][0].x == 100, foo[0][1].y == 5, etc. But GCC spits out a lot of errors. If anyone could provide the proper syntax that'd be great. EDIT: Okay, I tried this: struct foo { const char *x; int y; }; struct foo bar[2][] = { { { "A", 1 }, { "B", 2 }, { NULL, -1 }, }, { { "AA", 11 }, { "BB", 22 }, { NULL, -1 }, }, { { "ZZ", 11 }, { "YY", 22 }, { NULL, -1 }, }, { { "XX", 11 }, { "UU", 22 }, { NULL, -1 }, }, }; But GCC gives me "elements of array bar have incomplete type" and "excess elements in array initializer".

  Read the article

• why nResult != nConvertedLen,when use CComBSTR;

  - by hxboxy

  CComBSTR wsData = (char*)pvData; when constuct CComBSTR,call A2WBSTR,but sometimes nResult != nConvertedLen,just 1/20. why? inline BSTR A2WBSTR(_In_opt_ LPCSTR lp, int nLen = -1) { if (lp == NULL || nLen == 0) return NULL; USES_CONVERSION_EX; BSTR str = NULL; #pragma warning(push) #pragma warning(disable: 6385) int nConvertedLen = MultiByteToWideChar(_acp_ex, 0, lp, nLen, NULL, NULL); #pragma warning(pop) int nAllocLen = nConvertedLen; if (nLen == -1) nAllocLen -= 1; // Don't allocate terminating '\0' str = ::SysAllocStringLen(NULL, nAllocLen); if (str != NULL) { int nResult; nResult = MultiByteToWideChar(_acp_ex, 0, lp, nLen, str, nConvertedLen); ATLASSERT(nResult == nConvertedLen); if(nResult != nConvertedLen) { SysFreeString(str); return NULL; } } return str; }

  Read the article

• Is there a method to retrieve the file name of a class?

  - by Dran Dane

  Hello Is there a method to retrieve the file name of a class? Specifically I would like to create a static method (CreateLink) in a base class (BasePage) to automatically return the path and filename of the page called. I code in .C# ASP.NET private const string TEMPLATE = "~/One.aspx"; public static HyperLink CreateLink() { HyperLink link = new HyperLink(); link.Text = "Click here"; link.NavigateUrl = String.Format(TEMPLATE); return link; } Is it possible to avoid the use of TEMPLATE hardcoded variable? Is it possible to retrieve the One.aspx path from file name and location?

  Read the article

• Sending some byte at time

  - by user1417815

  I'm trying to figure out way to send some amount of text from the string ech time until it reach the end of the string, example: const char* the_string = "hello world, i'm happy to meet you all. Let be friends or maybe more, but nothing less" Output: hello world Output: , i'm happy to meet you all. Output: Let be friends or maybe more Output: , but nothing less stop: no more bytes to send. the problem i have searched google, but didn't understand the examples, i spent 4 days trying find a good way, also that sendt 5 bytes at time, but in case there is less, then send them until you are at the end of the string. please help me out guys, i will accept a C or C++ way, as long it works and well explained.

  Read the article

• How to copy a structure with pointers to data inside (so to copy pointers and data they point to)?

  - by Kabumbus

  so I have a structure like struct GetResultStructure { int length; char* ptr; }; I need a way to make a full copy of it meaning I need a copy to have a structure with new ptr poinnting on to copy of data I had in original structure. Is It any how possible? I mean any structure I have which contains ptrs will have some fields with its lengths I need a function that would copy my structure coping all ptrs and data they point to by given array of lengthes... Any cool boost function for it? Or any way how to create such function?

  Read the article

• I make this for balancing paranthesis of equation but i think it is wrong check and correct it

  - by muhammadlodhi

  int main(){ char i,input[30],close,open; for(i=0;i<='.';i++){ printf("enter equation"); scanf("%c",input[i]); if(input[i]=='(') input++; input[i]=open; else if(input[i]==')') input[i]--; input[i]=close; else if(open[i]==close[i]) { printf("paranthesis are balance"); } else printf("paranthesis are not balance"); } getch(); return 0; }

  Read the article

• how to specify a pointer to an overloaded function?

  - by davka

  I want to pass an overloaded function to the std::for_each() algorithm. e.g.: void f(char c); void f(int i); std::string s("example"); std::for_each(s.begin(), s.end(), f); I'd expect the compiler to resolve f() by the iterator type. Apparently, it (gcc 4.1.2) doesn't do it. So, how can I specify which f() I want? thanks a lot

  Read the article

• C++: Delete a struct?

  - by Rosarch

  I have a struct that contains pointers: struct foo { char* f; int* d; wchar* m; } I have a vector of shared pointers to these structs: vector<shared_ptr<foo>> vec; vec is allocated on the stack. When it passes out of scope at the end of the method, its destructor will be called. (Right?) That will in turn call the destructor of each element in the vector. (Right?) Does calling delete foo delete just the pointers such as foo.f, or does it actually free the memory from the heap?

  Read the article

• sorting set of five string in alphabetical oder throwing warning?

  - by rost rost

  sorting set of five string in alphabetical oder throwing warning ?my code is below please help me to fix it #include<stdio.h> #include<string.h> int main() { char a[5][20],t[20]; int i,j; printf("enter 5 string\n") scanf("%s",a); for(i=1;i<5;i++) { for(j=1;j<5;j++) { if(strcmp(a[j-1],a[j])>0) { strcpy (t,a[j-1]); strcpy (a[j-1],a[j]); strcpy(a[j],t); } } } for(i=1;i<5;i++) printf("%s\n",a[i]); } ~

  Read the article

< Previous Page | 226 227 228 229 230 231 232 233 234 235 236 237  | Next Page >