出现一个错误，不明白为什么？

lovechang1314

TypeError: Unable to cast object of type 'MeteoInfoC.Legend.PolygonBreak' to type 'MeteoInfoC.Legend.PolyLineBreak'.来源网址：http://hi.baidu.com/meteoinfo/item/3fa7c11ca5374e6170d5e8c4绘制等值线图，网址中绘制了阴影，我把一下代码更改rainLayer = DrawMeteoData.CreateShadedLayer(gData, ls, "Precipitation", "Rain")
rainLayer = DrawMeteoData.CreateContourLayer(gData, ls, "Precipitation", "Rain")
lgs内容如下<MeteoInfo file="preci" type="LegendScheme">  <LegendScheme FieldName="Precipitation6h" LegendType="UniqueValue" ShapeType="Polyline" BreakNum="10" HasNoData="False" MinValue="0" MaxValue="13" UNDEF="9999">    <Breaks>      <Break Caption="1" StartValue="1" EndValue="1" Color="#6E00DC" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="Square" SymbolColor="#6E00DC" SymbolInterval="1" />      <Break Caption="2" StartValue="2" EndValue="2" Color="#00A0FF" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="UpTriangle" SymbolColor="#00A0FF" SymbolInterval="1" />      <Break Caption="3" StartValue="3" EndValue="3" Color="#00C8C8" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="DownTriangle" SymbolColor="#00C8C8" SymbolInterval="1" />      <Break Caption="4" StartValue="4" EndValue="4" Color="#00DC00" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="Diamond" SymbolColor="#00DC00" SymbolInterval="1" />      <Break Caption="5" StartValue="5" EndValue="5" Color="#A0E632" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="XCross" SymbolColor="#A0E632" SymbolInterval="1" />      <Break Caption="6" StartValue="6" EndValue="6" Color="#E6DC32" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="Plus" SymbolColor="#E6DC32" SymbolInterval="1" />      <Break Caption="7" StartValue="7" EndValue="7" Color="#E6AF2D" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="Star" SymbolColor="#E6AF2D" SymbolInterval="1" />      <Break Caption="8" StartValue="8" EndValue="8" Color="#F08228" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="StarLines" SymbolColor="#F08228" SymbolInterval="1" />      <Break Caption="9" StartValue="9" EndValue="9" Color="#FA3C3C" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="Pentagon" SymbolColor="#FA3C3C" SymbolInterval="1" />      <Break Caption="10" StartValue="10" EndValue="10" Color="#F00082" DrawShape="True" Size="1" Style="Solid" DrawSymbol="False" SymbolSize="8" SymbolStyle="UpSemiCircle" SymbolColor="#F00082" SymbolInterval="1" />    </Breaks>  </LegendScheme></MeteoInfo>

请帮忙分析一下错误原因呀？

MeteoInfo

你需要一个Polygon的lgs文件

lovechang1314

MeteoInfo 发表于 2014-10-21 12:07
你需要一个Polygon的lgs文件

绘制的是等值线，为什么不是polyline而是polygon呢

MeteoInfo

lovechang1314 发表于 2014-10-21 12:38
绘制的是等值线，为什么不是polyline而是polygon呢

你把你整段代码贴出来看看

lovechang1314

1. 设置
   
2. interpSet = InterpolationSetting(60,140,-20,60,160,160,"IDW_Radius",2,1)
   
3. 
   
4. #---- 设置图例
   
5. ls = LegendScheme(ShapeTypes.Polygon)
   
6. #ls.ImportFromXMLFile(LegendDir + "rain1.lgs")
   
7. ls.ImportFromXMLFile(homedir + "preci.lgs")
   
8. 
   
9. #ls = LegendManage.CreateLegendSchemeFromGridData(press,LegendType.UniqueValue, ShapeTypes.Polyline, ref hasUndefData)
   
10. #print ls
    
11. 
    
12. #---- 设置MeteoDataInfo
    
13. mid = MeteoDataInfo()
    
14. 
    
15. #---- 循环
    
16. while sTime <= eTime:   
    
17.   inFile = sTime.ToString("yyMMddHH") + ".000"
    
18.   print inFile
    
19.   #---- 打开MICAPS数据文件
    
20.   mid.OpenMICAPSData(DataDir + inFile)
    
21.   #---- 获取6小时降水量站点数据
    
22.   stData = mid.GetStationData("WindSpeed")
    
23.   #---- 将站点数据差值为格点数据
    
24.   gData = DrawMeteoData.InterpolateData(stData, interpSet)
    
25.   #ls = LegendManage.CreateLegendSchemeFromGridData(gData, LegendType.GraduatedColor,ShapeTypes.Polygon)
    
26.   #---- 生成6小时降水量图层
    
27.   rainLayer = DrawMeteoData.CreateContourLayer(gData, ls, "WindSpeed", "Wind")
    
28.   rainLayer.IsMaskout = True
    
29.   #---- 添加图层
    
30.   mapFrame.AddLayer(rainLayer)
    
31.   print "Display finished"
    
32.   #---- 调整图层顺序（以避免压盖）
    
33.   mapFrame.MoveLayerToBottom(rainLayer)
    
34.   #---- 设置标题名称
    
35.   title = "      全国降水量实况图\n6小时降水量 (" + sTime.ToString("yyyy-MM-dd HH:00") + ")"
    
36.   aText.SetLabelText(title)   
    
37.   #---- 设置图例名称
    
38.   aLegend.Title = "降水量（毫米）"
    
39.   #---- 绘制图形
    
40.   mapLayout.PaintGraphics()
    
41.   #---- 输出图形为文件
    
42.   outFile = "Prec_" + sTime.ToString("yyyyMMddHH") + ".png"
    
43.   print outFile
    
44.   #mapLayout.ExportToPicture("E:\\Temp\" + outFile)
    
45.   #---- 删除6小时降水量图层
    
46.   if sTime < eTime:
    
47.     mapFrame.RemoveLayer(rainLayer)
    
48.   #---- 时间加6小时
    
49.   sTime = sTime.AddHours(6)
    
50. 
    
51. #---- 显示程序窗体（只是为了看效果，自动运行时不需要）
    
52. #Application.Run(myApp)
    
53. myApp.Show()

复制代码

MeteoInfo

lovechang1314 发表于 2014-10-21 14:45

第5行有问题，你自己仔细看看：
ls = LegendScheme(ShapeTypes.Polygon)