protected internal override Expression VisitCase(CaseExpression cex)
{
AppendNewLine(Indentation.Inner);
sb.Append("CASE");
AppendNewLine(Indentation.Inner);
for (int i = 0, n = cex.Whens.Count; i < n; i++)
{
When when = cex.Whens[i];
sb.Append("WHEN ");
Visit(when.Condition);
sb.Append(" THEN ");
Visit(when.Value);
AppendNewLine(Indentation.Same);
}
if (cex.DefaultValue != null)
{
sb.Append("ELSE ");
Visit(cex.DefaultValue);
AppendNewLine(Indentation.Outer);
}
sb.Append("END");
AppendNewLine(Indentation.Outer);
return(cex);
}
Expression MakeSqlValue(Expression exp)
{
if (exp == null)
{
return(null !);
}
if (!inSql || !IsBooleanExpression(exp))
{
return(exp);
}
if (exp.NodeType == ExpressionType.Constant)
{
switch (((bool?)((ConstantExpression)exp).Value))
{
case false: return(new SqlConstantExpression(0, exp.Type));
case true: return(new SqlConstantExpression(1, exp.Type));
case null: return(new SqlConstantExpression(null, exp.Type));
}
throw new InvalidOperationException("Entity");
}
if (!IsSqlCondition(exp))
{
return(exp);
}
var result = new CaseExpression(new[] { new When(exp, new SqlConstantExpression(true)) }, new SqlConstantExpression(false));
return(exp.Type.IsNullable() ? result.Nullify() : result);
}
protected internal virtual Expression VisitCase(CaseExpression cex)
{
var newWhens = Visit(cex.Whens, w => VisitWhen(w));
var newDefault = Visit(cex.DefaultValue);
if (newWhens != cex.Whens || newDefault != cex.DefaultValue)
{
return(new CaseExpression(newWhens, newDefault));
}
return(cex);
}
protected internal override Expression VisitCase(CaseExpression cex)
{
var newWhens = Visit(cex.Whens, w => VisitWhen(w));
var newDefault = MakeSqlValue(Visit(cex.DefaultValue));
if (newWhens != cex.Whens || newDefault != cex.DefaultValue)
{
return(new CaseExpression(newWhens, newDefault));
}
return(cex);
}
protected virtual bool CompareCase(CaseExpression a, CaseExpression b)
{
return(CompareList(a.Whens, b.Whens, CompareWhen) &&
Compare(a.DefaultValue, b.DefaultValue));
}