遇到奇怪问题，探讨探讨

Sub countnumber()

Dim pMap As IMap
Dim pMxDocument As IMxDocument
Set pMxDocument = ThisDocument
Set pMap = pMxDocument.FocusMap

Dim pRasterlayer As IRasterLayer
Set pRasterlayer = pMap.Layer(0)

Dim pRaster As IRaster
Set pRaster = pRasterlayer.Raster

Dim pRasBC As IRasterBandCollection
Set pRasBC = pRaster

Dim pRasterBand As IRasterBand
Set pRasterBand = pRasBC.Item(0)

' This example shows the usage of the IRawPixels interface to
' Read and write pixels to a raster band that is passed in.
' QI for the IRawPixels interface
Dim pRawPixels As IRawPixels
Set pRawPixels = pRasterBand

' QI for the IRasterProps interface to get height and width
Dim pProps As IRasterProps
Set pProps = pRaster

Dim pPnt As IPnt
Set pPnt = New DblPnt
pPnt.SetCoords pProps.Width, pProps.Height

' Use the RawPixels interface to create a new PixelBlock
Dim pPixelBlock As IPixelBlock
Set pPixelBlock = pRawPixels.CreatePixelBlock(pPnt)
' Create a new point to specify where to begin reading, then read
' Note:the origin is specified in pixel (or image) coordinates
Dim pOrigin As IPnt
Set pOrigin = New DblPnt
pOrigin.SetCoords 0, 0
pRawPixels.Read pOrigin, pPixelBlock

' get the variant SafeArray from the pixelblock
Dim vPixels As Variant
vPixels = pPixelBlock.SafeArray(0)

Dim i As Long, j As Long, sum As Long, value As Double

value = InputBox("请输入元胞的值：", "输入框")

For i = 0 To pProps.Width - 1
For j = 0 To pProps.Height - 1
If vPixels(i, j) = value Then sum = sum + 1
Next
Next

MsgBox "此栅格图层中值为" ; value ; "的元胞有" ; sum ; "个"

End Sub