Field

• Get all fields

              //ITable iTable = ifc as ITable;
              //int fieldCount = iTable.Fields.FieldCount;     
              int num = ifc.Fields.FieldCount;//字段的个数    
              for (int i = 0; i < num; i++)
              {
                  string target = ifc.Fields.get_Field(i).AliasName;
                  IField field = ifc.Fields.get_Field(i);//iTable.Fields.get_Field(i);
                  if ((field.Type == esriFieldType.esriFieldTypeOID) || field.Type == esriFieldType.esriFieldTypeGeometry ||
                              field.Name.ToUpper() == "SHAPE_LENGTH" || field.Name.ToUpper() == "SHAPE_LENGTH()" ||
                              field.Name.ToUpper() == "SHAPE_AREA()" || field.Name.ToUpper() == "SHAPE_AREA" ||
                              field.Name.ToUpper() == "SHAPE.STAREA()" || field.Name.ToUpper() == "SHAPE.STLENGTH()")
                      continue;
                  else
                  {
                      string Name = ified.Name;
                      string AliasName = ified.AliasName;
                      esriFieldType Type = ified.Type;
                      int Length = ified.Length;
                      object DefaultValue = ified.DefaultValue;
                      bool IsNullable = ified.IsNullable;
                      int Precision = ified.Precision;
                      int Scale = ified.Scale;
                  }
              }

  • Add a field

                                IField addFied = new Field();
                                IFieldEdit editField = (IFieldEdit)addFied;
                                editField.Name_2 = fieldName;
                                //editField.AliasName_2 = "";
                                editField.Type_2 = esriFieldType.esriFieldTypeString;//esriFieldType.esriFieldTypeString
                                editField.Length_2 = length;
                                editField.Precision_2 = precision;
                                editField.DefaultValue_2 = "";
                                editField.IsNullable_2 = true;
                                ifc.AddField(addFied);

  • Delete field

                        int fieldIndex = m_feacls.Fields.FindField(name);//需要删除的字段名称
                        IField delField = iFields.get_Field(fieldIndex);
                        ifc.DeleteField(delField);

  • Add more fields

                ESRI.ArcGIS.Geodatabase.IObjectClassDescription objectClassDescription = new ESRI.ArcGIS.Geodatabase.FeatureClassDescriptionClass();
                ESRI.ArcGIS.Geodatabase.IFields fields = null;
                // if a fields collection is not passed in then supply our own
                if (fields == null)
                {
                    // create the fields using the required fields method
                    fields = objectClassDescription.RequiredFields;
                    ESRI.ArcGIS.Geodatabase.IFieldsEdit fieldsEdit = (ESRI.ArcGIS.Geodatabase.IFieldsEdit)fields; // Explicit Cast
    
                    ESRI.ArcGIS.Geodatabase.IField fieldBSM = new ESRI.ArcGIS.Geodatabase.FieldClass();
                    ESRI.ArcGIS.Geodatabase.IFieldEdit fieldEditBSM = (ESRI.ArcGIS.Geodatabase.IFieldEdit)fieldBSM; // Explicit Cast
                    fieldEditBSM.Name_2 = "BSM";
                    fieldEditBSM.Type_2 = ESRI.ArcGIS.Geodatabase.esriFieldType.esriFieldTypeInteger;
                    fieldEditBSM.IsNullable_2 = true;
                    fieldEditBSM.AliasName_2 = "标识码";
                    fieldEditBSM.Editable_2 = true;
                    fieldsEdit.AddField(fieldBSM);
    
                    ESRI.ArcGIS.Geodatabase.IField fieldYSDM = new ESRI.ArcGIS.Geodatabase.FieldClass();
                    ESRI.ArcGIS.Geodatabase.IFieldEdit fieldEditYSDM = (ESRI.ArcGIS.Geodatabase.IFieldEdit)fieldYSDM; // Explicit Cast
                    fieldEditYSDM.Name_2 = "YSDM";
                    fieldEditYSDM.Type_2 = ESRI.ArcGIS.Geodatabase.esriFieldType.esriFieldTypeString;
                    fieldEditYSDM.IsNullable_2 = true;
                    fieldEditYSDM.AliasName_2 = "要素代码";
                    fieldEditYSDM.DefaultValue_2 = "0";
                    fieldEditYSDM.Editable_2 = true;
                    fieldEditYSDM.Length_2 = 10;
                    fieldsEdit.AddField(fieldYSDM);
                }
                ESRI.ArcGIS.Geodatabase.IFieldChecker fieldChecker = new ESRI.ArcGIS.Geodatabase.FieldCheckerClass();
                ESRI.ArcGIS.Geodatabase.IEnumFieldError enumFieldError = null;
                ESRI.ArcGIS.Geodatabase.IFields validatedFields = null;
                fieldChecker.ValidateWorkspace = (ESRI.ArcGIS.Geodatabase.IWorkspace)workspace;
                fieldChecker.Validate(fields, out enumFieldError, out validatedFields);//检查字段的有效性，最终结果用validatedFields

• Field Calculator

              Geoprocessor gp = new Geoprocessor();
              try
              {
                  CalculateField c = new CalculateField();
                  c.in_table = m_ifc as ITable;
                  c.field = name;//需要计算的字段名
                  c.expression = richTextBox1.Text;//"!shape.area!"或"!ZLDWDM!+!QSDWDM!"或"!JBNTMJ!"注意感叹号的运用
                  c.expression_type = "PYTHON";
                  gp.Execute(c, null);
              }
              catch
              {
                  label7.Text = gp.GetMessage(3);
                  MessageBox.Show(gp.GetMessage(3));
              }