public static void Render <T>(IEnumerable <ResultOrderingModel> orderBy, StringBuilder sb)
{
var olist = orderBy?.ToList();
if ((olist == null) || (olist.Count == 0))
{
return;
}
sb.Append(" ORDER BY ");
for (var i = 0; i < olist.Count; i++)
{
if (i > 0)
{
sb.Append(", ");
}
var order = olist[i];
var propchain = ExpressionsHelper.GetPropertiesChainText <T>(ExpressionsHelper.RemoveConvert(order.Expression));
if (string.IsNullOrWhiteSpace(propchain))
{
throw new InvalidOperationException($"Invalid OrderBy expression {order.Expression}");
}
var tabAndCol = DotPathHelper.SplitToEntityAndAttribute(propchain);
sb.Append($"[{tabAndCol.Item1}].[{tabAndCol.Item2}]");
sb.Append(order.Ascending ? " ASC" : " DESC");
}
sb.AppendLine();
}
public IQueryBuilder <T> Join <T2>(Expression <Func <T, T2> > expression)
{
var path = ExpressionsHelper.GetPropertiesChainText <T>(expression);
if (string.IsNullOrWhiteSpace(path))
{
throw new InvalidOperationException($"Invalid join expression {expression}");
}
Include(path);
return(this);
}
protected override IQuerySegment MapMemberExpression(MemberExpression expression)
{
var propChain = ExpressionsHelper.GetPropertiesChainText <T>(expression);
if (string.IsNullOrWhiteSpace(propChain))
{
throw new NotSupportedException($"Unsupported expression {expression}");
}
var tableAndColumn = DotPathHelper.SplitToEntityAndAttribute(propChain);
var tableAlias = tableAndColumn.Item1;
var column = tableAndColumn.Item2;
return(new ColumnSegment(tableAlias, column));
}
public void TestExpressionEvaluation()
{
Expression <Func <IEntity1, IEntity1> > exp = e => e.A.B.C;
var strExp = ExpressionsHelper.GetPropertiesChainText <IEntity1>(exp);
Assert.Equal("IEntity1.A.B.C", strExp);
Expression <Func <IEntity1, object> > oexp = e => e.X.Each().Y;
strExp = ExpressionsHelper.GetPropertiesChainText <IEntity1>(oexp);
Assert.Equal("IEntity1.X.Y", strExp);
oexp = e => e.X.OrderBy(i => i.Id).Each().Y;
strExp = ExpressionsHelper.GetPropertiesChainText <IEntity1>(oexp);
Assert.Null(strExp);
var v = 123;
Expression <Func <IEntity1, int> > iexp = e => v + 5;
strExp = ExpressionsHelper.GetPropertiesChainText <IEntity1>(iexp);
Assert.Null(strExp);
}
