public override DbExpression Visit(DbScanExpression expression)
{
var column = SoftDeleteAttribute.GetSoftDeleteColumnName(expression.Target.ElementType);
if (column != null)
{
var binding = DbExpressionBuilder.Bind(expression);
return(DbExpressionBuilder.Filter(
binding,
DbExpressionBuilder.NotEqual(
DbExpressionBuilder.Property(
DbExpressionBuilder.Variable(binding.VariableType, binding.VariableName),
column),
DbExpression.FromBoolean(true))));
}
else
{
return(base.Visit(expression));
}
}
public void TreeCreated(DbCommandTreeInterceptionContext interceptionContext)
{
if (interceptionContext.OriginalResult.DataSpace == DataSpace.SSpace)
{
var queryCommand = interceptionContext.Result as DbQueryCommandTree;
if (queryCommand != null)
{
var newQuery = queryCommand.Query.Accept(new SoftDeleteQueryVisitor());
interceptionContext.Result = new DbQueryCommandTree(
queryCommand.MetadataWorkspace,
queryCommand.DataSpace,
newQuery
);
}
var deleteCommand = interceptionContext.OriginalResult as DbDeleteCommandTree;
if (deleteCommand != null)
{
var column = SoftDeleteAttribute.GetSoftDeleteColumnName(deleteCommand.Target.VariableType.EdmType);
if (column != null)
{
var setClause =
DbExpressionBuilder.SetClause(
deleteCommand.Target.VariableType.Variable(deleteCommand.Target.VariableName).Property(column),
DbExpression.FromBoolean(true));
var update = new DbUpdateCommandTree(
deleteCommand.MetadataWorkspace,
deleteCommand.DataSpace,
deleteCommand.Target,
deleteCommand.Predicate,
new List <DbModificationClause> {
setClause
}.AsReadOnly(),
null);
interceptionContext.Result = update;
}
}
}
}
