方向：根据属性字段设置点图层中每个要素的符号方向和大小，

1 所有要素使用同一种符号---简单渲染

在图层属性---符号系统---单一符号中进行设置，首先设置符号，在后面的【高级】选项按钮中分别设置【旋转】和【大小】

【旋转】下拉框中选择对应字段，以及旋转方式，确定即可

【大小】下拉框中选择对应符号大小的字段，确认即可

2 要素根据字段值得不同采用不同的符号---使用唯一值渲染

图层属性中设置唯一值渲染，根据字段值得不同选择不同的符号，并在【高级】选项中设置【旋转】和【大小】，方法同上

显示效果如下：

ArcEngine提供了相应的接口进行设置，

IRotationRenderer设置旋转参数

ISizeRenderer设置大小参数

比如

IRotationRenderer pRotationRender = pSimRender as IRotationRenderer;
pRotationRender.RotationField = "ANGEL";
pRotationRender.RotationType = esriSymbolRotationType.esriRotateSymbolArithmetic;

ISizeRenderer pSizeRender = pSimRender as ISizeRenderer;
pSizeRender.SizeRendererFlags = (int)esriSizeRendererFlags.esriSizeRendererUseExpression;
pSizeRender.SizeRendererExpression = "[SIZE]";

简单渲染

    /// <summary>  
    /// 单一符号化  
    /// </summary>  
    /// <param name="pFeatLyr">渲染图层</param>  
    /// <param name="pRgbColor">渲染颜色</param>  
    private void SimpleRenderer(IFeatureLayer pFeatLyr, IMarkerSymbol markerSymbol)  
    {  
        try  
        {  
            esriGeometryType type = pFeatLyr.FeatureClass.ShapeType;  
            ISimpleRenderer pSimRender = new SimpleRendererClass();

            IColor pColor = this.GetColor(255, 0, 0);  
            if (type == esriGeometryType.esriGeometryPoint)  
            {  
                markerSymbol.Color = pColor;  
                markerSymbol.Size = 50;  
                pSimRender.Symbol = markerSymbol as ISymbol;  
                IRotationRenderer pRotationRender = pSimRender as IRotationRenderer;  
                pRotationRender.RotationField = "ANGEL";  
                pRotationRender.RotationType = esriSymbolRotationType.esriRotateSymbolArithmetic;

                ISizeRenderer pSizeRender = pSimRender as ISizeRenderer;  
                pSizeRender.SizeRendererFlags = (int)esriSizeRendererFlags.esriSizeRendererUseExpression;  
                pSizeRender.SizeRendererExpression = "\[SIZE\]";                    

            }

            IGeoFeatureLayer pGeoFeatLyr = pFeatLyr as IGeoFeatureLayer;  
            pGeoFeatLyr.Renderer = pSimRender as IFeatureRenderer;  
            this.axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGeography, null, null);  
            this.axTOCControl1.Update();  
        }  
        catch (Exception ex)  
        {  
        }  
    }

唯一值渲染

    /// <summary>  
    /// 多符号  
    /// </summary>  
    /// <param name="pFeaLyr"></param>  
    /// <param name="fieldname"></param>  
    private void UniqueValueRender(IFeatureLayer pFeaLyr, string fieldname)  
    {  
        IGeoFeatureLayer pGeoFeatLyr = pFeaLyr as IGeoFeatureLayer;  
        ITable pTable = pFeaLyr as ITable;  
        IUniqueValueRenderer pUniqueValueRender = new UniqueValueRendererClass();

        int intFieldNumber = pTable.FindField(fieldname);  
        pUniqueValueRender.FieldCount = 1;//设置唯一值符号化的关键字段为一个  
        pUniqueValueRender.set\_Field(0, fieldname);//设置唯一值符号化的第一个关键字段

        //根据渲染字段的值的个数，设置一组随机颜色，如某一字段有5个值，则创建5个随机颜色与之匹配  
        IQueryFilter pQueryFilter = new QueryFilterClass();  
        bool bSuccess = false;  
        IColor pNextUniqueColor = this.GetColor(255, 0, 0);  
        //查询字段的值  
        pQueryFilter = new QueryFilterClass();  
        pQueryFilter.AddField(fieldname);  
        ICursor pCursor = pTable.Search(pQueryFilter, true);  
        IRow pNextRow = pCursor.NextRow();  
        int codeValue = 0;  
        IRowBuffer pNextRowBuffer = null;

        while (pNextRow != null)  
        {  
            pNextRowBuffer = pNextRow as IRowBuffer;  
            codeValue = Convert.ToInt32(pNextRowBuffer.get\_Value(intFieldNumber));//获取渲染字段的每一个值  
            IMarkerSymbol pMarkerSymbol = null;

            switch (pGeoFeatLyr.FeatureClass.ShapeType)  
            {  
                case esriGeometryType.esriGeometryPoint:  
                    {  
                        string symbolname = "";  
                        switch (codeValue)  
                        {  
                            case 1:  
                                symbolname = "飞机场";  
                                break;  
                            case 2:  
                                symbolname = "箭头";  
                                break;  
                            case 3:  
                                symbolname = "房屋";  
                                break;

                        }  
                        pMarkerSymbol = ServerSymbolUtilty.GetItemFromServerStyle(symbolFile, "Marker Symbols", symbolname).Item as IMarkerSymbol;  
                        pMarkerSymbol.Color = pNextUniqueColor;  
                        pUniqueValueRender.AddValue(codeValue.ToString(), "", pMarkerSymbol as ISymbol);//添加渲染字段的值和渲染样式  
                        pNextRow = pCursor.NextRow();  
                        break;  
                    }  
            }  
        }  
        IRotationRenderer pRotationRender = pUniqueValueRender as IRotationRenderer;  
        pRotationRender.RotationField = "ANGEL";  
        pRotationRender.RotationType = esriSymbolRotationType.esriRotateSymbolArithmetic;

        ISizeRenderer pSizeRender = pUniqueValueRender as ISizeRenderer;  
        pSizeRender.SizeRendererFlags = (int)esriSizeRendererFlags.esriSizeRendererUseExpression;  
        pSizeRender.SizeRendererExpression = "\[SIZE\]";

        pGeoFeatLyr.Renderer = pUniqueValueRender as IFeatureRenderer;  
        axMapControl1.Refresh();  
        axTOCControl1.Update();  
    }

这里仅是点符号的渲染，其他渲染类似，代码比较乱，仅供参考，