void CalcLength(

string tmpshp)

        {

            

var expression = 

"

float(!SHAPE.LENGTH@YARDS!)

";

            CalculateField cgridX = 

new CalculateField(tmpshp, 

"

Length

", expression);

            cgridX.expression_type = 

"

PYTHON

";

            IGeoProcessorResult gpResX = gp.Execute(cgridX, 

null) 

as IGeoProcessorResult;

            Console.WriteLine(

"

计算长度

");

        }

  var gp = new ESRI.ArcGIS.Geoprocessor.Geoprocessor();

            gp.AddOutputsToMap = true;

            gp.OverwriteOutput = true;

            gp.TemporaryMapLayers = true;