/// <summary>
/// Searches through all changes that caused a concurrency conflict in the DataContext and
/// compiles an error message listing all the conflicts on all tables and each member (field) that caused the conflicts.
/// This method should be called after having called SubmitChanges on a DataContext and where a ChangeConflictException
/// has occured.
/// </summary>
/// <returns></returns>
public static string GetLinqToSqlChangeConflictErrorMessage(DataContext dataContext)
{
StringBuilder result = new StringBuilder();
result.AppendLine("LINQ to SQL optimistic concurrency error:");
result.AppendLine();
foreach (ObjectChangeConflict conflict in dataContext.ChangeConflicts)
{
MetaTable metatable = dataContext.Mapping.GetTable(conflict.Object.GetType());
result.AppendLine($"Conflict Table name: {metatable.TableName}");
object entityInConflict = conflict.Object;
PropertyInfo surrogateKey = EntityReaderWindows.GetLinqToSqlEntitySurrogateKey(entityInConflict.GetType());
bool containsIdentityColumn = EntityReaderWindows.IsLinqToSqlEntityPropertyIdentityColumn(surrogateKey);
object surrogateKeyValue = surrogateKey.GetValue(entityInConflict, null);
result.Append($"Conflict Entity ID: {surrogateKeyValue}");
foreach (MemberChangeConflict memberConflict in conflict.MemberConflicts)
{
object currentValue = memberConflict.CurrentValue;
object originalValue = memberConflict.OriginalValue;
object databaseValue = memberConflict.DatabaseValue;
MemberInfo member = memberConflict.Member;
result.AppendLine($"Conflict Member: {member.Name}");
result.AppendLine($"Current Value: {currentValue}");
result.AppendLine($"Original Value {originalValue}");
result.AppendLine($"Database Value: {databaseValue}");
}
result.AppendLine();
}
return(result.ToString());
}
/// <summary>
/// Determines the primary key of an entity type. The first primary key found on the entity type i.e.
/// the assumption is made that the entity type only has one primary key, which is the surrogate key.
/// </summary>
/// <typeparam name="E">The entity type i.e. the table whose surrogate key needs to be determined.</typeparam>
/// <returns>Retruns the PropertyInfo corresponding to the column which is the surrogate key for the specified entity type.</returns>
public virtual PropertyInfo GetEntitySurrogateKey(Type entityType)
{
return(EntityReaderWindows.GetLinqToSqlEntitySurrogateKey(entityType));
}
/// <summary>
/// Determines whether a property is an identity column.
/// </summary>
/// <param name="p"></param>
/// <returns>Returns true if the property is an identity column.</returns>
public virtual bool IsIdentityColumn(PropertyInfo p)
{
return(EntityReaderWindows.IsLinqToSqlEntityPropertyIdentityColumn(p));
}
/// <summary>
/// Determines the primary key of an entity type. The first primary key found on the entity type i.e.
/// the assumption is made that the entity type only has one primary key, which is the surrogate key.
/// </summary>
/// <typeparam name="E">The entity type i.e. the table whose surrogate key needs to be determined.</typeparam>
/// <returns>Retruns the PropertyInfo corresponding to the column which is the surrogate key for the specified entity type.</returns>
public virtual PropertyInfo GetEntitySurrogateKey <E>()
{
return(EntityReaderWindows.GetLinqToSqlEntitySurrogateKey <E>());
}
