protected virtual ReadOnlyCollection <DbColumnAssignment> VisitColumnAssignments(
ReadOnlyCollection <DbColumnAssignment> assignments)
{
List <DbColumnAssignment> alternate = null;
for (int i = 0, n = assignments.Count; i < n; i++)
{
DbColumnAssignment assignment = VisitColumnAssignment(assignments[i]);
if (alternate == null && assignment != assignments[i])
{
alternate = assignments.Take(i).ToList();
}
if (alternate != null)
{
alternate.Add(assignment);
}
}
if (alternate != null)
{
return(alternate.AsReadOnly());
}
return(assignments);
}
protected virtual DbColumnAssignment VisitColumnAssignment(DbColumnAssignment ca)
{
DbColumnExpression c = (DbColumnExpression)Visit(ca.Column);
Expression e = Visit(ca.Expression);
return(UpdateColumnAssignment(ca, c, e));
}
protected DbColumnAssignment UpdateColumnAssignment(
DbColumnAssignment ca, DbColumnExpression c, Expression e)
{
if (c != ca.Column || e != ca.Expression)
{
return(new DbColumnAssignment(c, e));
}
return(ca);
}
protected override DbColumnAssignment VisitColumnAssignment(DbColumnAssignment ca)
{
ca = base.VisitColumnAssignment(ca);
Expression expression = ca.Expression;
DbNamedValueExpression nv = expression as DbNamedValueExpression;
if (nv != null)
{
expression = new DbNamedValueExpression(nv.Name, ca.Column.DbType, nv.Value);
}
return(this.UpdateColumnAssignment(ca, ca.Column, expression));
}
protected DbColumnAssignment UpdateColumnAssignment(
DbColumnAssignment ca, DbColumnExpression c, Expression e)
{
if (c != ca.Column || e != ca.Expression)
return new DbColumnAssignment(c, e);
return ca;
}
protected virtual DbColumnAssignment VisitColumnAssignment(DbColumnAssignment ca)
{
DbColumnExpression c = (DbColumnExpression)Visit(ca.Column);
Expression e = Visit(ca.Expression);
return UpdateColumnAssignment(ca, c, e);
}