从文本文件中读取数字到C中的数组。

I'm a programming noob so please bear with me.

我是编程新手，所以请容忍我。

I'm trying to read numbers from a text file into an array. The text file, "somenumbers.txt" simply holds 16 numbers as so "5623125698541159".

我试着把文本文件中的数字读入数组。somenumbers文本文件。”txt"只包含16个数字，如"5623125698541159"。

#include <stdio.h>
main()
{

    FILE *myFile;
    myFile = fopen("somenumbers.txt", "r");

    //read file into array
    int numberArray[16];
    int i;

    for (i = 0; i < 16; i++)
    {
        fscanf(myFile, "%d", &numberArray[i]);
    }

    for (i = 0; i < 16; i++)
    {
        printf("Number is: %d\n\n", numberArray[i]);
    }


}

The program doesn't work. It compiles but outputs:

程序不工作。它编译但输出:

Number is: -104204697

号码是:-104204697

Number is: 0

数:0

Number is: 4200704

号码是:4200704

Number is: 2686672

号码是:2686672

Number is: 2686728

号码是:2686728

Number is: 2686916

号码是:2686916

Number is: 2004716757

号码是:2004716757

Number is: 1321049414

号码是:1321049414

Number is: -2

数量:2

Number is: 2004619618

号码是:2004619618

Number is: 2004966340

号码是:2004966340

Number is: 4200704

号码是:4200704

Number is: 2686868

号码是:2686868

Number is: 4200798

号码是:4200798

Number is: 4200704

号码是:4200704

Number is: 8727656

号码是:8727656

Process returned 20 (0x14) execution time : 0.118 s Press any key to continue.

进程返回20 (0x14)执行时间:0.118秒按任意键继续。

5 个解决方案

#1

change to

改变

fscanf(myFile, "%1d", &numberArray[i]);

#2

5623125698541159 is treated as a single number (out of range of int on most architecture). You need to write numbers in your file as

5623125698541159被视为单个数字(在大多数体系结构上超出int范围)。您需要在文件as中写入数字

5 6 2 3 1 2 5  6 9 8 5 4 1 1 5 9  

for 16 numbers.

16的数字。

If your file has input

如果你的文件有输入

5,6,2,3,1,2,5,6,9,8,5,4,1,1,5,9 

then change %d specifier in your fscanf to %d,.

然后在fscanf中更改%d说明符到%d。

  fscanf(myFile, "%d,", &numberArray[i] );  

Here is your full code after few modifications:

这是经过一些修改后的完整代码:

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

int main(){

    FILE *myFile;
    myFile = fopen("somenumbers.txt", "r");

    //read file into array
    int numberArray[16];
    int i;

    if (myFile == NULL){
        printf("Error Reading File\n");
        exit (0);
    }

    for (i = 0; i < 16; i++){
        fscanf(myFile, "%d,", &numberArray[i] );
    }

    for (i = 0; i < 16; i++){
        printf("Number is: %d\n\n", numberArray[i]);
    }

    fclose(myFile);

    return 0;
}

#3

for (i = 0; i < 16; i++)
{
    fscanf(myFile, "%d", &numberArray[i]);
}

This is attempting to read the whole string, "5623125698541159" into &numArray[0]. You need spaces between the numbers:

这是尝试读取整个字符串，“5623125698541159”到&numArray[0]。你需要数字之间的空格:

5 6 2 3 ...

#4

Loop with %c to read the stream character by character instead of %d.

使用%c循环以按字符读取流字符，而不是按%d。

#5

There are two problems in your code:

您的代码中有两个问题:

• the return value of scanf must be checked
• 必须检查scanf的返回值。
• the %d conversion does not take overflows into account (blindly applying *10 + newdigit for each consecutive numeric character)
• %d转换不考虑溢出(盲目地为每个连续的数字字符应用*10 +新数字)

The first value you got (-104204697) is equals to 5623125698541159 modulo 2^32; it is thus the result of an overflow (if int where 64 bits wide, no overflow would happen). The next values are uninitialized (garbage from the stack) and thus unpredictable.

你第一个值(-104204697)等于-104204697模2 ^ 32;因此，它是溢出的结果(如果int宽度为64位，则不会发生溢出)。下一个值未初始化(来自堆栈的垃圾)，因此不可预测。

The code you need could be (similar to the answer of BLUEPIXY above, with the illustration how to check the return value of scanf, the number of items successfully matched):

您需要的代码可以是(类似上面BLUEPIXY的答案，说明如何检查scanf的返回值，成功匹配的项目数量):

#include <stdio.h>

int main(int argc, char *argv[]) {
    int i, j;
    short unsigned digitArray[16];
    i = 0;
    while (
        i != sizeof(digitArray) / sizeof(digitArray[0])
     && 1 == scanf("%1hu", digitArray + i)
    ) {
        i++;
    }
    for (j = 0; j != i; j++) {
        printf("%hu\n", digitArray[j]);
    }
    return 0;
}