帮助在Visual Studio 2008中打开文件

Question

我试图使用Visual Studio 2008，因为我在XCode中打开文件时出现问题。我对VS很陌生，但这些都是我采取的步骤。我创建了一个新项目，选择了Win32控制台应用程序，空项目。我的代码是：

// C_test.cpp : Defines the entry point for the console application. 
// 
#include <stdio.h> 
#include <stdlib.h> 

int main(void) 
{ 
    printf("Hello"); 
    FILE *filePtr; 

    filePtr = fopen("test.txt", "r"); 
    if (filePtr == NULL) 
    { 
     fprintf(stderr, "Can't open \"test\"\n"); 
     exit(EXIT_FAILURE); 
    } 
    else 
    { 
     int x; 

     printf("File open successful\n"); 
     /* read one character at a time until EOF is reached */ 
     while ((x = fgetc(filePtr)) != EOF) 
     { 
     //printf("%c", x); 
     fprintf(stderr, "%x\n",x); 
     } 
    } 
    fclose(filePtr); 
    system("pause"); 

    return 0; 
} 

东西似乎并不正确，因为我的错误列表是：

>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(9) : error C2275: 'FILE' : illegal use of this type as an expression 
1>  c:\program files\microsoft visual studio 9.0\vc\include\stdio.h(69) : see declaration of 'FILE' 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(9) : error C2065: 'filePtr' : undeclared identifier 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(11) : error C2065: 'filePtr' : undeclared identifier 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(11) : warning C4047: '=' : 'int' differs in levels of indirection from 'FILE *' 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(12) : error C2065: 'filePtr' : undeclared identifier 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(12) : warning C4047: '==' : 'int' differs in levels of indirection from 'void *' 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(23) : error C2065: 'filePtr' : undeclared identifier 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(23) : warning C4047: 'function' : 'FILE *' differs in levels of indirection from 'int' 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(23) : warning C4024: 'fgetc' : different types for formal and actual parameter 1 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(29) : error C2065: 'filePtr' : undeclared identifier 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(29) : warning C4047: 'function' : 'FILE *' differs in levels of indirection from 'int' 
1>c:\documents and settings\jon\my documents\visual studio 2008\projects\c_test\c_test\main.c(29) : warning C4024: 'fclose' : different types for formal and actual parameter 1 
1>Build log was saved at "file://c:\Documents and Settings\jon\My Documents\Visual Studio 2008\Projects\C_test\C_test\Debug\BuildLog.htm" 
1>C_test - 6 error(s), 6 warning(s) 
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== 

有什么想法？对不起，如果这是一个> c：\ documents和settings \ jon \ my文件\ visual studio 2008 \ projects \ c_test \ c_test \ main.c（9）：error C2275：'FILE'：非法使用此类型作为表达式 1> c：\ program files \ microsoft visual studio 9.0 \ vc \ include \ stdio.h（69）：参见'FILE'声明 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（9）：error C2065：'filePtr'：未声明的标识符 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c （11）：error C2065：'filePtr'：未声明的标识符 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（11）：warning C4047：'= '：'int'与'FILE *'的间接级别不同' 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c （12）：error C2065：'filePtr'：未声明的标识符 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（12）：warning C4047：'= ='：'int'与'void *'的间接级别不同1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（23）：error C2065 ：'filePtr'：未声明的标识符 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（23）：warning C4047：'function'：'FILE *'与“int”的间接级别不同 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（23）：warning C4024：'fgetc'：不同类型1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（29）：error C2 for formal and actual parameter 1 065：'filePtr'：未声明的标识符 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（29）：warning C4047：'function'：'FILE * '与'int'的间接程度不同 1> c：\ documents and settings \ jon \ my documents \ visual studio 2008 \ projects \ c_test \ c_test \ main.c（29）：warning C4024：'fclose'：different 1>生成日志保存在“file：// c：\ Documents and Settings \ jon \ My Documents \ Visual Studio 2008 \ Projects \ C_test \ C_test \ Debug \ BuildLog.htm”中 1 > C_test - 6个错误，6个警告 ==========构建：0成功，1失败，0最新，0跳过======== ==

有什么想法？谢谢！

Answer 1

可以在C.

在任何代码前的范围{}的顶部只声明变量在C++中，你可以在任何地方申报。因此，要么将您的文件名更改为test.cpp或将您的第一个printf移至FILE * fileptr声明下方。

int main(void) 
{ 
    FILE *filePtr; 
    printf("Hello");