ExcelFile.ColFromIndex Method

Overloads

ExcelFile.ColFromIndex(Int32, Int32)

This is the column (1 based) for a given ColIndex. You can use this together with ColCountInRow(Int32) and ColToIndex(Int32, Int32) to iterate faster on a block. Or you can call LoopOverUsedRange for a method that does the looping for you using those methods.

Syntax

Namespace: FlexCel.Core

public abstract Int32 ColFromIndex(Int32 row, Int32 colIndex)

Parameters

<-> Parameter Type Description
row Int32 Row (1 based)
colIndex Int32 The index on the column list for the row. (1 based)

Returns

The column (1 based) corresponding to the index when the index is inside the bounds. If the index is <= 0 or the index is > ColCountInRow(Int32), it will return 0.

Examples

Instead of writing:

    int RowCount = xls.RowCount;
    int ColCount = xls.ColCount;
    for (int row = 1; row <= RowCount; row++)
    {
        for (int col = 1; col <= ColCount; col++) //It would be faster to use ColCountInRow. See https://doc.tmssoftware.com/flexcel/net/guides/performance-guide.html#avoid-calling-colcount
        {
            DoSomething(row, col);
        }
    }

You can use:

    int RowCount = xls.RowCount;
    for (int row = 1; row <= RowCount; row++)
    {
        int ColCountInRow = xls.ColCountInRow(row);
        for (int colIndex = 1; colIndex <= ColCountInRow; colIndex++)
        {
            DoSomething(row, xls.ColFromIndex(row, colIndex));
        }
    }

To loop on all the existing cells on a range you can use:

    // Loop at most until the last used row in the sheet.
    // If LastRow is for example 1.000.000, but there are only
    // 3 used rows, it makes no sense to loop over all the empty rows after row 3.
    int LastUsedRow = Math.Min(LastRow, xls.RowCount);

    for (int row = FirstRow; row <= LastUsedRow; row++)
    {
        int LastCIndex = xls.ColToIndex(row, LastColumn);
        int LastColFromIndex = xls.ColFromIndex(row, LastCIndex);
        if (LastColFromIndex > LastColumn || LastColFromIndex == 0) // LastColumn does not exist.
        {
            LastCIndex--;
        }
        if (LastCIndex == 0) continue; // This row is empty. Move to the next row.

        int XF = -1;
        for (int cIndex = xls.ColToIndex(row, FirstColumn); cIndex <= LastCIndex; cIndex++)
        {
            DoSomething(row, xls.ColFromIndex(row, cIndex), xls.GetCellValueIndexed(row, cIndex, ref XF));
        }
    }

Note that this example is the implementation of LoopOverUsedRange, so you might want to directly call LoopOverUsedRange instead of pasting this example in your code.

See also

ExcelFile.ColFromIndex(Int32, Int32, Int32)

This is the column (1 based) for a given ColIndex and sheet. You can use this together with ColCountInRow(Int32) and ColToIndex(Int32, Int32) to iterate faster on a block. Or you can call LoopOverUsedRange for a method that does the looping for you using those methods.

Syntax

Namespace: FlexCel.Core

public abstract Int32 ColFromIndex(Int32 sheet, Int32 row, Int32 colIndex)

Parameters

<-> Parameter Type Description
sheet Int32 Sheet where we are working. It might be different from ActiveSheet.
row Int32 Row (1 based)
colIndex Int32 The index on the column list for the row. (1 based)

Returns

The column (1 based) corresponding to the index when the index is inside the bounds. If the index is <= 0 or the index is > ColCountInRow(Int32), it will return 0.

Examples

Instead of writing:

    int RowCount = xls.RowCount;
    int ColCount = xls.ColCount;
    for (int row = 1; row <= RowCount; row++)
    {
        for (int col = 1; col <= ColCount; col++) //It would be faster to use ColCountInRow. See https://doc.tmssoftware.com/flexcel/net/guides/performance-guide.html#avoid-calling-colcount
        {
            DoSomething(row, col);
        }
    }

You can use:

    int RowCount = xls.RowCount;
    for (int row = 1; row <= RowCount; row++)
    {
        int ColCountInRow = xls.ColCountInRow(row);
        for (int colIndex = 1; colIndex <= ColCountInRow; colIndex++)
        {
            DoSomething(row, xls.ColFromIndex(row, colIndex));
        }
    }

To loop on all the existing cells on a range you can use:

    // Loop at most until the last used row in the sheet.
    // If LastRow is for example 1.000.000, but there are only
    // 3 used rows, it makes no sense to loop over all the empty rows after row 3.
    int LastUsedRow = Math.Min(LastRow, xls.RowCount);

    for (int row = FirstRow; row <= LastUsedRow; row++)
    {
        int LastCIndex = xls.ColToIndex(row, LastColumn);
        int LastColFromIndex = xls.ColFromIndex(row, LastCIndex);
        if (LastColFromIndex > LastColumn || LastColFromIndex == 0) // LastColumn does not exist.
        {
            LastCIndex--;
        }
        if (LastCIndex == 0) continue; // This row is empty. Move to the next row.

        int XF = -1;
        for (int cIndex = xls.ColToIndex(row, FirstColumn); cIndex <= LastCIndex; cIndex++)
        {
            DoSomething(row, xls.ColFromIndex(row, cIndex), xls.GetCellValueIndexed(row, cIndex, ref XF));
        }
    }

Note that this example is the implementation of LoopOverUsedRange, so you might want to directly call LoopOverUsedRange instead of pasting this example in your code.

See also