c - Visual Studio 2015 显示调试断言失败

Question

我制作了一个简单的文件读取程序，可以在 DEV C gcc 编译器中成功运行，但显示错误调试断言失败。我搜了一下，12天前有人问过同样的问题，答案表明他的错误在于声明

if (file = fopen (name, "w+") == NULL) {
  ...
}    

并将这两个语句分开

file = fopen(name, "w+");

if (fp == NULL) { ...}    

我的代码

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
int main()
{

    int nos = 0, noc = 0, nol = 0;
    char ch;
    FILE *fp;
    fp = fopen("Sarju.txt", "r");
    while (1)
    {
        ch = fgetc(fp);
        if (ch == NULL)
        {
            printf("The file didn't opened\n");
            break;
        }
        if (ch == EOF)
            break;
        noc++;
        if (ch == ' ')
            nos++;
        if (ch == '\n')
            nol++;
    }
    if (ch != NULL)
        fclose(fp);
    printf("Number of Space : %d\nNumber of Characters : %d\nNumber of lines : %d\n", nos, noc, nol);
    _getch();
    return 0;
}    `

我的错误

Debug Assertion failed! Program: ...o 2015\Projects\Let Us C Solutions\Debug\Let Us C Solutions.exe File: minkernel\crts\src\appcrt\stdio\fgetc.cpp Line: 43 Expression: stream.valid() For information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts. (Press Retry to debug the application)

Answer 1

您的代码有几个问题。更正后的代码为:

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>

int main()
{
    int nos = 0, noc = 0, nol = 0;
    int ch; /* `int`, not `char` */
    FILE *fp;
    fp = fopen("Sarju.txt", "r");
    while (1)
    {
        /*ch = fgetc(fp); After the below `if`, not here */
        if (fp == NULL) /* `fp`, not `ch` */
        {
            printf("The file didn't opened\n");
            break;
        }
        ch = fgetc(fp);
        if (ch == EOF)
            break;
        noc++;
        if (ch == ' ')
            nos++;
        if (ch == '\n')
            nol++;
    }
    if (fp != NULL) /* `fp`, not `ch` */
        fclose(fp);
    printf("Number of Space : %d\nNumber of Characters : %d\nNumber of lines : %d\n", nos, noc, nol);
    _getch();
    return 0;
}

1. 我使用了 int，因为 fgetc 返回的是 int，而不是 char。
2. 您应该检查 fp 是否不是 NULL，而不是 ch。
3. ch = fgetc(fp); 位置错误。