Question

当我编译此SDL代码时，我收到此错误：

SDL_DEV.cpp:60:2: error: expected unqualified-id before ‘if’


if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
  ^
SDL_DEV.cpp:64:2: error: expected unqualified-id before ‘else’
  else
  ^
Makefile:21: recipe for target 'all' failed
make: *** [all] Error 1

（我正在使用安装了SDL 2.0.5的Linux中的g ++编译）

以下是完整的源代码

#include <SDL2/SDL.h>
#include <stdio.h>


const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;

int main( int argc, char* args[] )
{

    SDL_Window* window = NULL;


    SDL_Surface* screenSurface = NULL;


    if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
    {
        printf( "SDL could not initialize! SDL_Error: %s\n", SDL_GetError() );
    }
    else
    {

        window = SDL_CreateWindow( "SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN );
        if( window == NULL )
        {
            printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
        }
        else
        {

            screenSurface = SDL_GetWindowSurface( window );


            SDL_FillRect( screenSurface, NULL, SDL_MapRGB( screenSurface->format, 0xFF, 0xFF, 0xFF ) );


            SDL_UpdateWindowSurface( window );


            SDL_Delay( 2000 );
        }
    }


    SDL_DestroyWindow( window );


    SDL_Quit();

    return 0;
}   
    SDL_Window* window = NULL;


    SDL_Surface* screenSurface = NULL;


    if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
    {
        printf( "SDL could not initialize! SDL_Error: %s\n", SDL_GetError() );
    }
    else
    {

        window = SDL_CreateWindow( "SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN );
        if( window == NULL )
        {
            printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
        }
        else
        {

            screenSurface = SDL_GetWindowSurface( window );


            SDL_FillRect( screenSurface, NULL, SDL_MapRGB( screenSurface->format, 0xFF, 0xFF, 0xFF ) );


            SDL_UpdateWindowSurface( window );


            SDL_Delay( 2000 );
        }
    }


    SDL_DestroyWindow( window );


    SDL_Quit();

    return 0;
}

我不明白为什么我会收到此错误，因为我之前已在其他计算机上编译过它。如果有人能帮助我解决这个问题，我会很高兴。谢谢。

Answer 1

问题解决了，我想当我从Windows平台上复制它时，我没有看到额外的代码。

SDL应用程序错误：'if'之前的预期unqualified-id

1 个答案: