ColorCells.ts

/**
 * This sample demonstartes how to iterate over a selected range and set cell property. It colors each cell within the selected range with a random color.
 */
function main(workbook: ExcelScript.Workbook) {

    const syncStart = new Date().getTime();
    // Get selected range
    const range = workbook.getSelectedRange();
    const rows = range.getRowCount();
    const cols = range.getColumnCount();
    console.log("Start");

    // Color each cell with random color
    for (let row = 0; row < rows; row++) {
        for (let col = 0; col < cols; col++) {
            range
                .getCell(row, col)
                .getFormat()
                .getFill()
                .setColor(`#${Math.random().toString(16).substr(-6)}`);
        }
    }
    console.log("End");
    const syncEnd = new Date().getTime();
    console.log("Completed, took: " + (syncEnd - syncStart) / 1000 + " Sec");

}