How to create a raster stretch renderer

public IRasterRenderer StretchRenderer(ESRI.ArcGIS.Geodatabase.IRasterDataset
    rasterDataset)
{
    try
    {
        //Define the from and to colors for the color ramp.
        IRgbColor fromColor = new RgbColorClass();
        fromColor.Red = 255;
        fromColor.Green = 0;
        fromColor.Blue = 0;
        IColor toColor = new RgbColorClass();
        fromColor.Red = 0;
        fromColor.Green = 255;
        fromColor.Blue = 0;
        //Create the color ramp.
        IAlgorithmicColorRamp colorRamp = new AlgorithmicColorRampClass();
        colorRamp.Size = 255;
        colorRamp.FromColor = fromColor;
        colorRamp.ToColor = toColor;
        bool createColorRamp;
        colorRamp.CreateRamp(out createColorRamp);
        //Create a stretch renderer.
        IRasterStretchColorRampRenderer stretchRenderer = new
            RasterStretchColorRampRendererClass();
        IRasterRenderer rasterRenderer = (IRasterRenderer)stretchRenderer;
        //Set the renderer properties.
        IRaster raster = rasterDataset.CreateDefaultRaster();
        rasterRenderer.Raster = raster;
        rasterRenderer.Update();
        stretchRenderer.BandIndex = 0;
        stretchRenderer.ColorRamp = colorRamp;
        //Set the stretch type.
        IRasterStretch stretchType = (IRasterStretch)rasterRenderer;
        stretchType.StretchType =
            esriRasterStretchTypesEnum.esriRasterStretch_StandardDeviations;
        stretchType.StandardDeviationsParam = 2;
        return rasterRenderer;
    }
    catch (Exception ex)
    {
        System.Diagnostics.Debug.WriteLine(ex.Message);
        return null;
    }
}

Public Function StretchRenderer(ByVal rasterDataset As ESRI.ArcGIS.GeodataMyBase.IRasterDataset) As IRasterRenderer
    Try
    'Define the from and to colors for the color ramp.
    Dim fromColor As IRgbColor = New RgbColorClass()
    fromColor.Red = 255
    fromColor.Green = 0
    fromColor.Blue = 0
    Dim toColor As IColor = New RgbColorClass()
    fromColor.Red = 0
    fromColor.Green = 255
    fromColor.Blue = 0
    
    'Create the color ramp.
    Dim colorRamp As IAlgorithmicColorRamp = New AlgorithmicColorRampClass()
    colorRamp.Size = 255
    colorRamp.FromColor = fromColor
    colorRamp.ToColor = toColor
    Dim createColorRamp As Boolean
    colorRamp.CreateRamp( createColorRamp)
    
    'Create a stretch renderer.
    Dim stretchRenderer As IRasterStretchColorRampRenderer = New RasterStretchColorRampRendererClass()
    Dim rasterRenderer As IRasterRenderer = CType(stretchRenderer, IRasterRenderer)
    
    'Set the renderer properties.
    Dim raster As IRaster = rasterDataset.CreateDefaultRaster()
    rasterRenderer.Raster = raster
    rasterRenderer.Update()
    stretchRenderer.BandIndex = 0
    stretchRenderer.ColorRamp = colorRamp
    
    'Set the stretch type.
    Dim stretchType As IRasterStretch = CType(rasterRenderer, IRasterStretch)
    stretchType.StretchType = esriRasterStretchTypesEnum.esriRasterStretch_StandardDeviations
    stretchType.StandardDeviationsParam = 2
    
    Return rasterRenderer
    Catch ex As Exception
    System.Diagnostics.Debug.WriteLine(ex.Message)
    Return Nothing
    End Try
End Function