Label Expression Question

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Label Expression Question	Calvin Smith	Nov 23, 2004
Re: Label Expression Question	Tim Whiteaker	Nov 23, 2004
Re: Label Expression Question	Calvin Smith	Nov 23, 2004
Re: Label Expression Question	Tim Whiteaker	Nov 23, 2004
Re: Label Expression Question	Calvin Smith	Nov 23, 2004
Re: Label Expression Question	Tim Whiteaker	Nov 23, 2004
Re: Label Expression Question	Calvin Smith	Nov 23, 2004

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Subject	Label Expression Question
Author	Calvin Smith
Date	Nov 23, 2004
Message	I would like to label a set of polygons based on their SHAPE_area. I have tried using the int([SHAPE_area) in ArcMap and it works great but when I bring it over to a mapcontrol in ArcObjects, I am getting a 'Type mismatch' error. Has anyone seen this? Thanks!
	Dim pGeoLayer As IGeoFeatureLayer Set pGeoLayer = MapControl1.Layer(0) Dim pLabelEngine As ILabelEngineLayerProperties pGeoLayer.AnnotationProperties.Clear Set pLabelEngine = New LabelEngineLayerProperties Dim sRoomArea As String sRoomArea = "[" & "SHAPE_area" & "]" Dim sLabel As Integer sLabel = Int(sRoomArea) 'MsgBox sLabel 'pLabelEngine.Expression = sRoomArea pLabelEngine.Expression = sLabel pLabelEngine.IsExpressionSimple = True Dim pBOLayerProps As IBasicOverposterLayerProperties Set pBOLayerProps = New BasicOverposterLayerProperties pBOLayerProps.NumLabelsOption = esriOneLabelPerShape Set pLabelEngine.BasicOverposterLayerProperties = pBOLayerProps pGeoLayer.AnnotationProperties.Add pLabelEngine pGeoLayer.DisplayAnnotation = True MapControl1.ActiveView.PartialRefresh esriViewGraphics, Nothing, Nothing

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Subject	Re: Label Expression Question
Author	Tim Whiteaker
Date	Nov 23, 2004
Message	The type mismatch is probably because pLabelEngine.Expression is expecting a String, and you are feeding it an Integer. Instead of declaring sLabel as an Integer, declare it as a string and use the expression below.
	Dim sLabel As String sLabel = "int([" & "SHAPE_area" & "])"
	Tim Whiteaker Research Associate The University of Texas at Austin

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Subject	Re: Label Expression Question
Author	Calvin Smith
Date	Nov 23, 2004
Message	When I do this, all of my values are '0'. The same command in ArcMap's label expression gives me the values I need.

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Subject	Re: Label Expression Question
Author	Tim Whiteaker
Date	Nov 23, 2004
Message	After you run the code, open the layer properties and look at the label expression in ArcMap. Did the code produce the same expression as when you type in the expression manually?
	Tim Whiteaker Research Associate The University of Texas at Austin

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Subject	Re: Label Expression Question
Author	Calvin Smith
Date	Nov 23, 2004
Message	Unfortunately so. I actually designed my ArcObjects expression to reflect the ArcMap expression. I am creating the code to change the labels in a standalone MapControl, so I can check the label expression afterwards. Thanks again for your help!

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Subject	Re: Label Expression Question
Author	Tim Whiteaker
Date	Nov 23, 2004
Message	The fact that all your labels come up as zero leads me to believe that an integer is still being fed as the label expression. For example, if the expression read int(myfield) then all labels would be zero, because "myfield" would be assumed to be a new variable, initialized as zero. int(0) = 0, so all labels would be zero. The code below is working for me. If you try the code below and it still doesn't work for you, then I'm stumped. Note that I'm testing this in ArcMap VBA, and I'm not using a MapControl (thus, the two lines involving the MapControl are different in the version I'm actually testing).
	Dim pGeoLayer As IGeoFeatureLayer Set pGeoLayer = MapControl1.Layer(0) Dim pLabelEngine As ILabelEngineLayerProperties pGeoLayer.AnnotationProperties.Clear Set pLabelEngine = New LabelEngineLayerProperties Dim sLabel As String sLabel = "int([" & "SHAPE_area" & "])" pLabelEngine.Expression = sLabel pLabelEngine.IsExpressionSimple = True Dim pBOLayerProps As IBasicOverposterLayerProperties Set pBOLayerProps = New BasicOverposterLayerProperties pBOLayerProps.NumLabelsOption = esriOneLabelPerShape Set pLabelEngine.BasicOverposterLayerProperties = pBOLayerProps pGeoLayer.AnnotationProperties.Add pLabelEngine pGeoLayer.DisplayAnnotation = True MapControl1.ActiveView.PartialRefresh esriViewGraphics, Nothing, Nothing
	Tim Whiteaker Research Associate The University of Texas at Austin

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Subject	Re: Label Expression Question
Author	Calvin Smith
Date	Nov 23, 2004
Message	That worked for me. My apotrophies and ')' were out of place. I double checked the syntax and it's working perfectly. Thanks for all the help on that.