自定义GP工具，如何设置ChoiceList参数?

inputParameter = new GPParameterClass();

inputParameter.DataType = new GPBooleanTypeClass();

var gpChoiceList = new GPFieldChoiceListClass();

var arr = new ArrayClass();

var gpDomain = new GPCodedValueDomain();

gpDomain.AddStringCode("snap", "捕捉");

gpDomain.AddStringCode("closed", "最近点");

gpChoiceList.MakeChoiceList(arr, gpDomain as IGPDomain);

inputParameter.ChoiceList = gpChoiceList;



// Value object is GPString

IGPString gpStringValue = new GPStringClass();

gpStringValue.Value = "捕捉";

inputParameter.Value = (IGPValue)gpStringValue;



// Set field name parameter properties

inputParameter.Direction = esriGPParameterDirection.esriGPParameterDirectionInput;

inputParameter.DisplayName = "加点方式";

inputParameter.Name = "add_type";

inputParameter.ParameterType = esriGPParameterType.esriGPParameterTypeOptional;

parameters.Add(inputParameter);