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File read / find - miss 1st line in file

mathewfer (32)
Hi,

I wrote the below code to find the line with "abc" as my parameter to strTosearch. I expected to the line 1st line but, this function always match the 2nd line. What am I missing here?

I wanted "found" to be "abc def hgi SSS".

Can someone please help to understand & fix this? Thanks.

Code in main()
String found=GetstringColSamLine("mytext.txt", "abc");

File name - mytext.txt
abc def hgi SSS
abc ppp yyy


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string GetstringColSamLine(string routerFileName, string strTosearch)
{
    string str;
    string line;
    string strone;
    unsigned long offset;

    ifstream fileToSearch;
    fileToSearch.open (routerFileName.c_str());
    if(fileToSearch)
    {
        while(getline(fileToSearch, line))
        {
            if ((offset=line.find(strTosearch, 0)) != string::npos)
            {
                strone=line;
            }
        }
    }
    fileToSearch.close();
    return(strone);
}


Mathew
ne555 (10692)
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        while(getline(fileToSearch, line))
            if (line.find(strTosearch, 0) != string::npos)
                return line;
vlad from moscow (6539)
Your loop does not stop when it finds the target string. So in fact strone will contain the last occurence of the target string.

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        while(getline(fileToSearch, line))
        {
            if ((offset=line.find(strTosearch, 0)) != string::npos)
            {
                strone=line;
            }
        }


You could either insert break statement inside the loop in the case when the target string is found or rewrite the condition of the loop.
Last edited on
mathewfer (32)
Hi

Thanks. That fixed the problem. I did not catch it was not coming from the loop.

So this is solved.

Thanks again.

Mathew
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