// This method will update the output parameter value with the additional area field.
public void UpdateParameters(IArray paramvalues, IGPEnvironmentManager pEnvMgr)
{
m_Parameters = paramvalues;
// Retrieve the input parameter value
IGPValue parameterValue = m_GPUtilities.UnpackGPValue(m_Parameters.get_Element(0));
// Get the derived output feature class schema and empty the additional fields. This will ensure you don't get duplicate entries.
IGPParameter3 derivedFeatures = (IGPParameter3)paramvalues.get_Element(2);
IGPFeatureSchema schema = (IGPFeatureSchema)derivedFeatures.Schema;
schema.AdditionalFields = null;
// If we have an input value, create a new field based on the field name the user entered.
if (parameterValue.IsEmpty() == false)
{
IGPParameter3 fieldNameParameter = (IGPParameter3)paramvalues.get_Element(1);
string fieldName = fieldNameParameter.Value.GetAsText();
// Check if the user's input field already exists
IField areaField = m_GPUtilities.FindField(parameterValue, fieldName);
if (areaField == null)
{
IFieldsEdit fieldsEdit = new FieldsClass();
IFieldEdit fieldEdit = new FieldClass();
fieldEdit.Name_2 = fieldName;
fieldEdit.Type_2 = esriFieldType.esriFieldTypeDouble;
fieldsEdit.AddField(fieldEdit);
// Add an additional field for the area values to the derived output.
IFields fields = fieldsEdit as IFields;
schema.AdditionalFields = fields;
}
}
}
/*
* Called each time the user changes a parameter in the tool dialog or Command Line.
* This updates the output data of the tool, which extremely useful for building models.
* After returning from UpdateParameters(), geoprocessing calls its internal validation routine checkng that a given set of parameter values
* are of the appropriate number, DataType, and value.
* This method will update the output parameter value with the unique field.
*/
public void UpdateParameters(IArray paramvalues, IGPEnvironmentManager pEnvMgr)
{
m_Parameters = paramvalues;
// Retrieve the input parameter value
IGPValue parameterValue = m_GPUtilities.UnpackGPValue(m_Parameters.get_Element(0));
// Retrieve the unique field parameter value
IGPParameter3 fieldNameParameter = (IGPParameter3)paramvalues.get_Element(3);
// Get the output feature class schema and empty the additional fields. This will ensure
// you don't get dublicate entries.
IGPParameter3 outputFeatures = (IGPParameter3)paramvalues.get_Element(2);
IGPFeatureSchema schema = (IGPFeatureSchema)outputFeatures.Schema;
schema.AdditionalFields = null;
// If we have an unique field value, create a new field based on the unique field name the user entered.
if (fieldNameParameter.Value.IsEmpty() == false)
{
string fieldName = fieldNameParameter.Value.GetAsText();
IField uniqueField = m_GPUtilities.FindField(parameterValue, fieldName);
IFieldsEdit fieldsEdit = new FieldsClass();
fieldsEdit.AddField(uniqueField);
IFields fields = fieldsEdit as IFields;
schema.AdditionalFields = fields;
}
}