In WebFormHTML class layoutgrid method, you can declare a boolean to check even or odd row and set the bgcolor ( ro style class) of the tr tag rendered.

 

For example

 

...

bEvenRow = false;

    for (row = 1; row <= rows; row++)

    {

        rowStr = int2str(row);

        if (dsos.cursor().RecId && moreRecords)

        {

        if ( bEvenRow == false)

        {

            #Output('<tr>');

            bEvenRow = true;

         }

         else

         {

                     #Output('<tr BGCOLOR="red">');

            bEvenRow = false;

 

         }

....

...

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