C# code to add a column to an existing MS Access Table.

Revised  post to correct the horrible code formatting.  Sorry....

public static void AddDAOTableColumn(string MDBfile, string tableName, string ColumnName, TypeCode dataType, Int32? columnSize, bool AutoNumber)

{

try

{

EnterProc(System.Reflection.MethodBase.GetCurrentMethod());

dao.DBEngine DBE = new dao.DBEngine();

dao.Database DB = DBE.OpenDatabase(MDBfile, false, false, "");

LogValue(string.Format("Opened Database: {0}", DB.Name));

dao.TableDef table = DB.TableDefs[tableName];

LogValue(string.Format("Found Table: {0}", tableName));

bool bAddColumn = true;

if (table != null)

{

foreach (dao.Field fld in table.Fields)

{

if (fld.Name == ColumnName)

{

bAddColumn = false;

break;

}

}

}

else

bAddColumn = false;

LogValue(string.Format("Table.{0} exists?:{1}", ColumnName, !bAddColumn));

if (bAddColumn)

{

dao.DataTypeEnum columnType;

switch (dataType)

{

case TypeCode.Boolean:

columnType = dao.DataTypeEnum.dbBoolean;

break;

case TypeCode.DateTime:

columnType = dao.DataTypeEnum.dbDate;

break;

case TypeCode.Int16:

columnType = dao.DataTypeEnum.dbInteger;                            

break;

case TypeCode.Int32:

columnType = dao.DataTypeEnum.dbLong;                            

break;

case TypeCode.Object:

columnType = dao.DataTypeEnum.dbMemo;

columnSize = null;

break;

case TypeCode.String:

if (columnSize <= 255)

columnType = dao.DataTypeEnum.dbText;

else

{

columnType = dao.DataTypeEnum.dbMemo;

columnSize = null;

}

break;

default:

columnType = dao.DataTypeEnum.dbText;

if (columnSize == null)

columnSize = 50;

break;

}

dao.Field newfield = new dao.Field();

newfield.Name = ColumnName;

newfield.Type = (short)columnType;

if (newfield.Type == (short) dao.DataTypeEnum.dbText)

newfield.AllowZeroLength = true;

if (columnSize != null)

newfield.Size = Convert.ToInt32(columnSize);

if (AutoNumber)

newfield.Attributes = (int)dao.FieldAttributeEnum.dbAutoIncrField;

table.Fields.Append(newfield);

table.Fields.Refresh();

DB.TableDefs.Refresh();

LogValue(string.Format("Created Column: {0}", newfield.Name));

DB.Close();

table = null;

newfield = null;

DB = null;

DBE = null;

}

ExitProc(System.Reflection.MethodBase.GetCurrentMethod());

}

catch (Exception ex)

{

ErrorLog(ex);

}

}