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How to read/write to an MS-Excel file??

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rajatC

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How to read/write to an MS-Excel file??

Dec 29th, 2007

How to output to an excel file and how to read from it??

i have done the writing part...to use "\t" for moving to next cell in same row and "\n" to move to next row...

and is there any special format to save that excel file..because when i save it with the extension .xls then it says every time i try to open it...

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the file is not known with this extension check whether it is corrupted.

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

.xls files are a proprietary (that's secret) format of microsoft.

For something portable, the best is "Comma Separated Values", or CSV.

So you would have say
1,2,3
hello,world
"and now, the news","for today"

If you save this text file with the extension .csv, then excel should be able to read it just fine.

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

ok
that was about the extension part..thanks..
now what about reading and writing in a excel file(.cvs)

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

> now what about reading and writing in a excel file(.cvs)
The same as you would for any other text file.

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

no i m not able to read from it with an ifstream fin("filename.cvs") object...

i told you how i m doing the writing part....
as excel file hav entries in cells so we need to advance the file pointer to next cell after reading one...how to do that...

we can do that by fout<<"\t" while writing with an object ofstream fout("filename.cvs")

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

Yes,
fout << field << "," << anotherField << endl;
So rather than using "\t" , use "," . It's that simple.

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Re: How to read/write to an MS-Excel file??

Dec 29th, 2007

post your code. The cells should be separated by comms, spaces or tabs. Each row separated with '\n'. I would use a combination of stringstream and getline() to read the file and separate its cells.

Something like this which assumes cells are separated with white space. A little different when separated by commas.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
std::string line;
std::ifstream in("filename here");
while( getline(line) )
{
    vector<string> cells;
    stringstream str(line);
    std::string cel;
    while( str >> cel)
    {
        cells.push_back(cel);
    }
    // now do something with the individual cells
}
std::string line;
std::ifstream in("filename here");
while( getline(line) )
{
    vector<string> cells;
    stringstream str(line);
    std::string cel;
    while( str >> cel)
    {
        cells.push_back(cel);
    }
    // now do something with the individual cells
}

Last edited by Ancient Dragon; Dec 29th, 2007 at 12:48 pm.

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jacki

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Re: How to read/write to an MS-Excel file??

Jan 5th, 2008

You cannot read and write .xls file using file manipulation functions in c/c++ because it is pre-formatted by excel. However, you can do such on a .csv file since it is just a in a "plain text" format like .txt. You can verify this by comparing the content of a .xls and .csv file using notepad. I`m telling you, you cannot read the content of .xls file.

However, if you are using c++ object oriented builder like borland c++ or visual c++, you can do what you want to do in the file. But you have to study how it work because the functions is very much different to the traditional c/c++. Take a look at this one for example, http://www.jcmiras.net/jcm/item/45/. You have to study object oriented functions like olepropertyget, variant, etc. In short, its hard but worthwhile.

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Re: How to read/write to an MS-Excel file??

Jan 5th, 2008

>>I`m telling you, you cannot read the content of .xls file.
It could be done but with great difficulty and probably very risky and for those reasons I wouldn't do it. The Microsoft Office SDK would be the best and safest solution but it too requires quite a bit of programming experience.

Last edited by Ancient Dragon; Jan 5th, 2008 at 11:57 pm.

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