/// <summary>
/// Returns whether or not that field's value is currently null/nothing
/// </summary>
/// <param name="fieldName">Field name as it appears in the data set</param>
/// <param name="mode">Link table or target table?</param>
/// <returns>True or false</returns>
public virtual bool IsFieldNull(string fieldName, XLinkItemAccessMode mode)
{
if (mode == XLinkItemAccessMode.CurrentTable)
{
return(IsFieldNull(fieldName));
}
if (ParentEntity is BusinessEntity entity)
{
fieldName = entity.GetInternalFieldName(fieldName, currentTargetRow.Table.TableName);
}
return(currentTargetRow[fieldName] == DBNull.Value);
}
/// <summary>
/// Returns the value of the specified field in the database
/// </summary>
/// <typeparam name="TField">The type of the field.</typeparam>
/// <param name="fieldName">Field name</param>
/// <param name="mode">Accessing a field in the parent (link) or target (child/foreign) table?</param>
/// <param name="ignoreNulls">
/// Should nulls be ignored and returned as such (true) or should the be turned into default
/// values (false)?
/// </param>
/// <returns>Value object</returns>
protected virtual TField ReadFieldValue <TField>(string fieldName, XLinkItemAccessMode mode, bool ignoreNulls = false)
{
if (mode == XLinkItemAccessMode.CurrentTable)
{
return(ReadFieldValue <TField>(fieldName));
}
if (!(ParentEntity is BusinessEntity entity))
{
throw new NullReferenceException("Parent entity is not a business entity.");
}
return(BusinessEntityHelper.GetFieldValue <TField>(entity, CurrentTargetRow.Table.DataSet, CurrentTargetRow.Table.TableName, fieldName, CurrentTargetRow, ignoreNulls));
}
/// <summary>Sets the value of a field in the database. This overload allows to specify whether the value is set in the master table, or the target table.</summary>
/// <param name="fieldName">Field name</param>
/// <param name="value">New value</param>
/// <param name="mode">Specifies whether we want to access the current (link) table ("Current") or the target table.</param>
/// <param name="forceUpdate">
/// Should the value be set, even if it is the same as before (and therefore set the dirty flag
/// despite that there were no changes)?
/// </param>
/// <returns>True or False</returns>
protected virtual bool SetFieldValue(string fieldName, object value, XLinkItemAccessMode mode, bool forceUpdate = false)
{
if (mode == XLinkItemAccessMode.CurrentTable)
{
return(SetFieldValue(fieldName, value, forceUpdate));
}
BusinessEntityHelper.CheckColumn(CurrentTargetRow.Table, fieldName);
if (!(ParentEntity is BusinessEntity entity))
{
throw new NullReferenceException("Parent entity is not a business entity.");
}
return(BusinessEntityHelper.SetFieldValue(entity, fieldName, value, CurrentTargetRow.Table.TableName, CurrentRow.Table.DataSet, CurrentTargetRow, forceUpdate));
}
/// <summary>
/// Returns the value of the specified field in the database
/// </summary>
/// <param name="fieldName">Field name</param>
/// <param name="mode">Accessing a field in the parent (link) or target (child/foreign) table?</param>
/// <param name="ignoreNulls">
/// Should nulls be ignored and returned as such (true) or should the be turned into default
/// values (false)?
/// </param>
/// <returns>Value object</returns>
protected virtual object GetFieldValue(string fieldName, XLinkItemAccessMode mode, bool ignoreNulls = false)
{
if (mode == XLinkItemAccessMode.CurrentTable)
{
return(GetFieldValue(fieldName));
}
var entity = ParentEntity as BusinessEntity;
if (entity == null)
{
throw new NullReferenceException("Parent entity is not a business entity.");
}
return(BusinessEntityHelper.GetFieldValue <object>(entity, CurrentTargetRow.Table.DataSet, CurrentTargetRow.Table.TableName, fieldName, CurrentTargetRow, ignoreNulls));
}
