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Reading CSV in VC++
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Join Date: Aug 2005
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>> VC++
That is the name of a specific compiler, not c programming language. Of course it supports c++, vector and push_back. You are writing a c++ program, if you want to use vector c++ class as I illustrated you have to include <vector> header file.
>>QString linecol
QString is a non-standard c++ class that M$ apparently developed for their compilers. I haven't used managed c++. the strings I posted are std::string from <string> header file, and maybe that is why you couldn't get it to work.
>> matrix_points[r][c] = line;
I mentioned this before -- you can't do this because matric_points is a 2d array of characters, not a 2d array of pointers
how is line declared? if it is a char array, then the code above will not work. If it is QString or std::string it still will not work. You are mixing c and c++ -- attempting to use c++ techniques on C string, or attempting to use C techniques on C++ string class. But I don't know which it is because you didn't post enough code.
That is the name of a specific compiler, not c programming language. Of course it supports c++, vector and push_back. You are writing a c++ program, if you want to use vector c++ class as I illustrated you have to include <vector> header file.
>>QString linecol
QString is a non-standard c++ class that M$ apparently developed for their compilers. I haven't used managed c++. the strings I posted are std::string from <string> header file, and maybe that is why you couldn't get it to work.
>> matrix_points[r][c] = line;
I mentioned this before -- you can't do this because matric_points is a 2d array of characters, not a 2d array of pointers
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C++ Syntax (Toggle Plain Text)
how is line declared? if it is a char array, then the code above will not work. If it is QString or std::string it still will not work. You are mixing c and c++ -- attempting to use c++ techniques on C string, or attempting to use C techniques on C++ string class. But I don't know which it is because you didn't post enough code.
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Join Date: Apr 2006
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Newbie Poster
Hi,
Yeah line is character array. This is how the following code looks like. Can you please find the area with mistakes and correct it.
QString matrix_points[6][8];
char line[255];
std::ifstream input_file("C:/NDA/NissanNewApplication/Dev/CommonErrorManager/Src/ErrorMessageList.csv");
input_file.clear();
input_file.seekg(0);
int r = 0, c = 0;
QString linecol, field;
while(input_file.getline(line, sizeof(line), '\n')) // to read lines
{
while(line != "")
{
linecol = line;
//linecol = linecol.stripWhiteSpace();
int pos = linecol.find(',');
field = linecol.left(pos);
if(pos > 0)
{
linecol = linecol.left(pos); // substr function does not work in VC++.
matrix_points[r][c] = linecol;
printf(matrix_points[r][c]);
linecol = linecol.left(pos+1);
++c;
}
else
{
matrix_points[r][c] = line;
linecol = "";
c = 0;
r++;
}
}
}
Yeah line is character array. This is how the following code looks like. Can you please find the area with mistakes and correct it.
QString matrix_points[6][8];
char line[255];
std::ifstream input_file("C:/NDA/NissanNewApplication/Dev/CommonErrorManager/Src/ErrorMessageList.csv");
input_file.clear();
input_file.seekg(0);
int r = 0, c = 0;
QString linecol, field;
while(input_file.getline(line, sizeof(line), '\n')) // to read lines
{
while(line != "")
{
linecol = line;
//linecol = linecol.stripWhiteSpace();
int pos = linecol.find(',');
field = linecol.left(pos);
if(pos > 0)
{
linecol = linecol.left(pos); // substr function does not work in VC++.
matrix_points[r][c] = linecol;
printf(matrix_points[r][c]);
linecol = linecol.left(pos+1);
++c;
}
else
{
matrix_points[r][c] = line;
linecol = "";
c = 0;
r++;
}
}
}
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Join Date: Aug 2005
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while(input_file.getline(line, sizeof(line), '\n')) // to read lines
{
linecol = line;
while(linecol != "")
{
int pos = linecol.find(',');
field = linecol.left(pos);
,,,std::string.substr(...) is similar to QString's mid method.
http://doc.trolltech.com/3.3/qstring.html
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Join Date: Apr 2006
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Hi Dragon,
Thanks for the reply. It works. Now the problem comes when I assign the matrix_points, which is of type QString to a variable in my application which is of ACE_WString Type, it gives a problem. What kind of typecasting method can we apply to overcome it?
Thanks & Regards,
Narender
Thanks for the reply. It works. Now the problem comes when I assign the matrix_points, which is of type QString to a variable in my application which is of ACE_WString Type, it gives a problem. What kind of typecasting method can we apply to overcome it?
Thanks & Regards,
Narender
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I don't know why you are using those odd-ball, non-standard c++ classes, maybe the university requires them? But anyway, looks like ACE_WString has a constructor that takes const char*, so just pass the right QString method that makes that conversion for you. You'll have to look it up.
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Join Date: Apr 2006
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This is what my whole code looks like. I am unable to locate the constructor which would help store into my codeText variable(ACE_WString) the value of matrix_points(QString). As you see the paramter in the function of my application requires me to pass ACE_WString type. Basically I want to assign QString type value to ACE_WString variable.
Follwoing is the error
Follwoing is the error
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Last edited by Dave Sinkula; Apr 18th, 2006 at 11:59 pm.
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Here is the version of ACE_WString whose second constructor takes char*. I have no way of knowing if that's the same one you are using.
QString has two methods that you may be interested in -- ascii() that returns char*, and unicode() that appears to make the ascii to unicode conversion for you.
I'm just sort of guessing about the above because I don't have either of those classes.
QString has two methods that you may be interested in -- ascii() that returns char*, and unicode() that appears to make the ascii to unicode conversion for you.
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I'm just sort of guessing about the above because I don't have either of those classes.
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Join Date: Apr 2006
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Hi Dragon,
Thank you. Actually I am able to manipulate the values from the csv file based on the row,column concept. I have now need to manipulate the values based on the header names. Concept being same as last, I would like to query based on column names.
Thanks & Regards,
Narender
Thank you. Actually I am able to manipulate the values from the csv file based on the row,column concept. I have now need to manipulate the values based on the header names. Concept being same as last, I would like to query based on column names.
Thanks & Regards,
Narender
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Join Date: Jul 2005
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Your dilema seems vague. I assume you have developed a 2 dimensional table of values like tableName[rowIndex][colIndex] and each column has a name/header/identifier. I further assume you want to be able to find a given column identified by it's name/header/identifier and be able to access the elements of the column to manipulate them in some fashion. If that's correct, then you can view the headers to be a row of data just like a row of values making up the body of the table itself and use a loop to search for the header/identifier you want. To do that you can hold the row index stable and vary the column index. Then to access all the values in the column you hold the column index stable and vary the row index.
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Join Date: Apr 2006
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Hi Lerner,
Thanks! So far I have done the same. My next step is to match the value till couple of columns in a row and if 2 rows are almost similar the value for the row which matches more closer should be displayed.
A glimpse of my code
Thanks & Regards
Thanks! So far I have done the same. My next step is to match the value till couple of columns in a row and if 2 rows are almost similar the value for the row which matches more closer should be displayed.
A glimpse of my code
C++ Syntax (Toggle Plain Text)
Thanks & Regards
Last edited by Dave Sinkula; Apr 19th, 2006 at 12:00 am.
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