[]
Gets or sets the number format code used by the data label.
This property returns the format code currently applied to the label value.
If the label does not define its own number format, it can use the inherited
format from its parent data labels. When no custom format is available, this
method returns "General".
string NumberFormat { get; set; }
Property NumberFormat As String
worksheet.Range["A1:B3"].Value = new object[,] {
{"Month", "Sales"},
{"Jan", 10},
{"Feb", 20}
};
IChart chart = worksheet.Shapes.AddChart(ChartType.ColumnClustered, 20, 20, 300, 200).Chart;
chart.SeriesCollection.Add(worksheet.Range["A1:B3"], RowCol.Columns);
IDataLabel dataLabel = chart.SeriesCollection[0].Points[0].DataLabel;
dataLabel.NumberFormat = "$#,##0.00";
string numberFormat = dataLabel.NumberFormat;