关于文件读取的问题求助

[xuxiaofeng055]

我想读入文件如下

__1123_2_0
_134_0_0_0
_________0

Ten character for each line, read two together. then replace the bank as -9

成格式如下
-9 11 23 2 0
1 34 0 0 0
-9 -9 -9 -9 0

试了多次全不成功，求助。

[xuxiaofeng055]

ifstream infile;
infile.open("temp.txt");
char bit[2];
int a = 0;
while(!infile.eof())
{
infile.read(bit, 2 * sizeof(char));
if(bit[0] == '\n') cout<<endl;
cout<<atoi(bit)<<" ";
a++;
}
cout<<endl<<a<<endl;

I used the above code only can get the results as below:
0 10 11 0
1 2 0 11 21
9

I do not know where is the 9 come from, and why the first char in the second line is shifted.

Thanks,

[lann64]

#include <iostream>
#include <string>
#include <fstream>
#include <cctype>
using namespace std;
int main()
{
    ifstream infile("temp.txt");
    string s;
    while (getline(infile,s))
    {
        int i=0;
        while (i<10)
        {
            if (s[i]=='_')
            {
                if (s[i+1]=='_') cout<<"-9";
                else
                    if (isdigit(s[i+1])) cout<<" "<<s[i+1];
                    else cout<<"  ";

            }
            else
            {
                if (isdigit(s[i])) cout<<s[i];
                else cout<<" ";
                if (isdigit(s[i+1])) cout<<s[i+1] ;
                else cout<<" ";
            }
            cout<<" ";
            i+=2;
        }
        cout<<endl;
    }
    return 0;
}

[lann64]

o,忘了关文件了。

#include <iostream>
#include <string>
#include <fstream>
#include <cctype>
using namespace std;
int main()
{
    ifstream infile("temp.txt");
    string s;
    while (getline(infile,s))
    {
        int i=0;
        while (i<10)
        {
            if (s[i]=='_')
            {
                if (s[i+1]=='_') cout<<"-9";
                else
                    if (isdigit(s[i+1])) cout<<" "<<s[i+1];
                    else cout<<"  ";

            }
            else
            {
                if (isdigit(s[i])) cout<<s[i];
                else cout<<" ";
                if (isdigit(s[i+1])) cout<<s[i+1] ;
                else cout<<" ";
            }
            cout<<" ";
            i+=2;
        }
        cout<<endl;
    }
    infile.close();
    return 0;
}

[baihacker]

__1123_2_0
_134_0_0_0
_________0

d:\>a
0 11 23 2 0 0
1 34 0 0 0 0
0 0 0 0 0 0

18

//要确保是windows系统,这样的话,/r/n才表示换行
#include <iostream>
#include <fstream>
using namespace std;

int main(void)
{
	ifstream infile; 
	infile.open("temp.txt", ios::in|ios::binary); 
	char bit[4]={0}; 
	int a = 0; 
	while(!infile.eof()) 
	{ 
			infile.read(bit, 2 * sizeof(char)); 
			if(!infile) break;
			if (bit[0] == '_') bit[0] = ' ';
		   
			cout <<atoi(bit) <<" ";
			  if(bit[0] == '\r') cout <<endl; 
			a++; 
	} 
	cout <<endl <<a <<endl; 
    return 0;
}

[baihacker]

正常情况下,输入文件应该是36Btye

30个字节的数据,还有三个\r\n

[xiaoyisnail]

#include <string>
#include <iostream>
#include <fstream>
using namespace std;

int main()
{

	fstream file("temp.txt", ios::in);
	if(!file)
	{
		cerr<<"error"<<endl;
		exit(1);
	}

	string line[128];//保存每一行
	int i = 0;
	while(getline(file, line[i]))//读文件
	{
		++i;
	}

	int line_num = i;

	file.clear();
	file.close();

	file.open("temp.txt", ios::out);//以写方式重新打开文件
	if(!file)
	{
		cerr<<"error"<<endl;
		exit(1);
	}

	i = 0;
	//对每一行进行格式处理
	while(i<line_num)
	{
		int j = 0;
		while(j<10)
		{
			if(line[i][j]=='_')
            {
                if(line[i][j+1]=='_') 
					file<<"-9";
                else if(isdigit(line[i][j+1]))
					file<<" "<<line[i][j+1];
            }
            else if(isdigit(line[i][j]))
            {
                file<<line[i][j]<<line[i][j+1];
            }
			if(j<8)
				file<<" ";
            j+=2;
		}
		file<<endl;
		++i;

	}

	return 0;
} 

[Cpp权哥]

直接把每行读取出来，两个两个字符取出来比较是不是一对空格，是就变成“-9”，不是就保持原样，然后加个空格，就完事了。
用标准C++写，不用考虑操作系统平台的问题。

#include <fstream>
#include <string>
using namespace std;

int main()
{
    char str[100], one[10]="  ";
    ifstream fin("infile.txt");
    ofstream fout("outfile.txt");
    while(fin.getline(str, sizeof(str))){
        int len = strlen(str);
        for(int i=0; i<len; i+=2){
            one[0] = str[i], one[1] = str[i+1];
            fout << (strcmp(one,"  ")==0?"-9":one) << " ";
        }
        fout << endl;
    }
    fin.close();
    fout.close();
    return 0;
}