样本记录将是这样的，
14/11/2014,Sh2345,423,10
12/12/2014,AV2345,242,20
从上面的记录我只需要
423,10
242,20
以下代码将为我提供所有行数和列数。
rowIndex = 0;
columnIndex = 0;
while(fgets(part,1024,fp) != NULL){
token = NULL;
while((token = strtok((token == NULL)?part:NULL,",")) != NULL){
if(rowIndex == 0){
columnIndex++;
}
for(idx = 0;idx<strlen(token);idx++){
if(token[idx] == '\n'){
rowIndex++;
break;
}
}
}
}
答案 0 :(得分：2)
如果你想使用strtok，我认为这是做这种事情的正确方法，因为fscanf在输入无效的情况下会出现问题，那么我认为这就是方法：
rowIndex = 0;
while (fgets(part, sizeof part, fp) != NULL)
{
char *token;
size_t partLength;
char *saveptr; // for strtok_r to store it's current state
partLength = strlen(part);
/* check if this is a complete line */
if (part[partLength - 1] == '\n')
rowIndex++;
columnIndex = 0;
token = strtok_r(part, ",", &saveptr);
while ((token = strtok_r(NULL, ",", &saveptr)) != NULL)
{
char *endptr;
/* if columnIndex >= 1 then we are in the right columns */
if (columnIndex >= 1)
values[columnIndex - 1] = strtol(token, &endptr, 10);
/* in case the conversion rejected some characters */
if ((*endptr != '\0') && (*endptr != '\n'))
values[columnIndex - 1] = -1; /* some invalid value (if it's possible) */
columnIndex++;
}
/* if we have columnIndex == 3, then we've read the two values */
if (columnIndex == 3)
printf("(%d, %d)\n", values[0], values[1]);
/* the last column will not be counted in the while loop */
columnIndex++;
}
如果行很长，sizeof part小到足以在它们之间留下一些,，你将需要一些不同的方法，但只要线条适合{{1你没事。
要将值读入数组，也许这可能有效：
part您还应注意，有时CSV文件中的字段包含int **fileToMatrix(const char *const filename, int *readRowCount, int *readColumnCount, int skipColumns)
{
char part[256];
FILE *file;
int rowIndex;
int columnIndex;
int index;
int **values;
file = fopen(filename, "r");
if (file == NULL)
return NULL;
values = NULL; /* calling realloc, it behaves like malloc if ptr argument is NULL */
rowIndex = 0;
while (fgets(part, sizeof part, file) != NULL)
{
char *token;
int **pointer;
char *saveptr; // for strtok_r to store it's current state
/* check if this is a complete line */
pointer = realloc(values, (1 + rowIndex) * sizeof(int *));
if (pointer == NULL)
goto abort;
values = pointer;
values[rowIndex] = NULL;
columnIndex = 0;
token = strtok_r(part, ",", &saveptr);
while ((token = strtok_r(NULL, ",", &saveptr)) != NULL)
{
columnIndex += 1;
/* if columnIndex > skipColumns - 1 then we are in the right columns */
if (columnIndex > (skipColumns - 1))
{
int value;
char *endptr;
int *currentRow;
int columnCount;
endptr = NULL;
value = strtol(token, &endptr, 10);
/* in case the conversion rejected some characters */
if ((endptr != NULL) && (*endptr != '\0') && (*endptr != '\n'))
value = -1;
/* ^ some invalid value (if it's possible) */
columnCount = columnIndex - skipColumns + 1;
currentRow = realloc(values[rowIndex], columnCount * sizeof(int));
if (currentRow == NULL)
goto abort;
currentRow[columnIndex - skipColumns] = value;
values[rowIndex] = currentRow;
}
}
/* the last column will not be counted in the while loop */
columnIndex++;
rowIndex++;
}
fprintf(stderr, "%d rows and %d columns parsed\n", rowIndex, columnIndex - skipColumns);
fclose(file);
*readRowCount = rowIndex;
*readColumnCount = columnIndex - skipColumns;
return values;
abort:
*readRowCount = -1;
*readColumnCount = -1;
for (index = rowIndex - 1 ; index >= 0 ; index--)
free(values[index]);
free(values);
fclose(file);
return NULL;
}
void freeMatrix(int **matrix, int rows, int columns)
{
int row;
for (row = 0 ; row < rows ; row++)
free(matrix[row]);
free(matrix);
}
void printMatrix(int **matrix, int rows, int columns)
{
int row;
int column;
for (row = 0 ; row < rows ; row++)
{
int *currentRow;
currentRow = matrix[row];
for (column = 0 ; column < columns ; column++)
printf("%8d", currentRow[column]);
printf("\n");
}
}
int main()
{
int **matrix;
int rows;
int columns;
matrix = fileToMatrix("data.dat", &rows, &columns, 2);
if (matrix != NULL)
{
printMatrix(matrix, rows, columns);
freeMatrix(matrix, rows, columns);
}
return 0;
}
或"引号，您可能希望将其从'返回的标记中删除，以避免strtok_r。
答案 1 :(得分：0)
int v1, v2;
while(fgets(part,1024,fp) != NULL){
sscanf(part, "%*[^,],%*[^,],%d,%d", &v1, &v2);//skip 2 field
//do stuff .. printf("%d,%d\n", v1, v2);
}
答案 2 :(得分：0)
int CheckMatrix(int Matrix, int Checkrow, int Checkvalue) /* to check whether the area code existing in the matrix*/
{
int i,j;
for(i=0;i<=Checkrow;i++)
{
if( Matrix[i][0]== Checkvalue)
{
return i;
}
else
{
return -1;
}
}
}
int **fileToMatrix(const char *const filename, int *readRowCount)
{
char part[256];
FILE *file;
int rowIndex;
int index;
int **values;
size_t partLength;
int v1,v2;
int CheckValue;
file = fopen(filename, "r");
if (file == NULL)
return NULL;
values = NULL; /* calling realloc, it behaves like malloc if ptr argument is NULL */
rowIndex = 0;
while (fgets(part, sizeof part, file) != NULL)
{
int **pointer;
/* check if this is a complete line */
pointer = realloc(values, (1 + rowIndex) * sizeof(int *));
if (pointer == NULL)
goto abort;
partLength = strlen(part);
/* check if this is a complete line */
if (part[partLength - 1] == '\n')
rowIndex++;
sscanf(part, "%*[^,],%*[^,],%d,%d", &v1, &v2);//skip 2 field to get the Area code and Distance
CheckValue = CheckMatrix(Values,rowIndex,V1); //Call the function to check whether the area code existing or not in the array
If (CheckValue!=-1) // If existing the current distace will add to the existing and increase the count of areacode.
{
Values[CheckValue][1]=Values[CheckValue][1]+V2;
Values[CheckValue][2]=Values[CheckValue][2];
}
else // If not existing will add to the matrix as new entry.
{
Values[CheckValue][0]=V1;
Values[CheckValue][1]=V2;
Values[CheckValue][2]=1;
}
}
return values;
abort:
*readRowCount = -1;
*readColumnCount = -1;
for (index = rowIndex - 1 ; index >= 0 ; index--)
free(values[index]);
free(values);
fclose(file);
return NULL;
}
void freeMatrix(int **matrix, int rows)
{
int row;
for (row = 0 ; row < rows ; row++)
free(matrix[row]);
free(matrix);
}
void printMatrix(int **matrix, int rows)
{
int row;
for (row = 0 ; row < rows ; row++)
{
for (column = 0 ; column < 4 ; column++)
{
if (column==3)
{
double Mean = double(matrix[row][1])/double(matrix[row][2]); /* To get the mean */
printf("%f",matrix[row][column];
}
printf("%d |", matrix[row][column]);
}
printf("\n");
}
}
# include <stdio.h>
int main()
{
int **matrix;
int rows;
matrix = fileToMatrix("data.dat", &rows);
if (matrix != NULL)
{
printf("|AreaCode|Total Distace|Area Count|Mean");
printf("------------------------------------------");
printMatrix(matrix, rows);
freeMatrix(matrix, rows);
}
return 0;
}