/// <summary>
/// Builds the query dictionary .
/// </summary>
/// <returns>The query.</returns>
/// <param name="model">Model.</param>
/// <typeparam name="TModel">The 1st type parameter.</typeparam>
public static IEnumerable <KeyValuePair <String, Object> > BuildQuery <TModel>(Expression <Func <TModel, bool> > model, bool stripNullChecks = false)
{
List <KeyValuePair <String, Object> > retVal = new List <KeyValuePair <string, Object> >();
var visitor = new HttpQueryExpressionVisitor(retVal);
visitor.Visit(model);
if (stripNullChecks)
{
retVal.RemoveAll(o => retVal.Any(c => c.Key == o.Key && c.Value != o.Value) && o.Value.Equals("!null"));
}
return(retVal);
}
/// <summary>
/// Visit method call
/// </summary>
protected override Expression VisitMethodCall(MethodCallExpression node)
{
switch (node.Method.Name)
{
case "Contains":
{
var parmName = this.ExtractPath(node.Object, false);
object parmValue = this.ExtractValue(node.Arguments[0]);
this.AddCondition(parmName, "~" + parmValue.ToString());
return(null);
}
case "StartsWith":
{
var parmName = this.ExtractPath(node.Object, false);
object parmValue = this.ExtractValue(node.Arguments[0]);
this.AddCondition(parmName, "^" + parmValue.ToString());
return(null);
}
case "Any":
{
var parmName = this.ExtractPath(node.Arguments[0], false);
// Process lambda
var result = new List <KeyValuePair <string, object> >();
var subQueryExpressionVisitor = new HttpQueryExpressionVisitor(result);
if (node.Arguments.Count == 2)
{
subQueryExpressionVisitor.Visit(node.Arguments[1]);
// Result
foreach (var itm in result)
{
this.AddCondition(String.Format("{0}.{1}", parmName, itm.Key), itm.Value);
}
return(null);
}
else
{
return(null);
}
}
default:
return(base.VisitMethodCall(node));
}
}
/// <summary>
/// Builds the query dictionary .
/// </summary>
/// <returns>The query.</returns>
/// <param name="model">Model.</param>
public static String BuildPropertySelector(LambdaExpression model)
{
var visitor = new HttpQueryExpressionVisitor(new List <KeyValuePair <string, object> >(), model.Parameters[0].Type);
return(visitor.ExtractPropertySelector(model));
}
/// <summary>
/// Visit method call optionally negating any values parsed
/// </summary>
private Expression VisitMethodCall(MethodCallExpression node, bool negate)
{
switch (node.Method.Name)
{
case "Contains":
{
if (node.Object == null && node.Method.DeclaringType == typeof(Enumerable))
{
return(this.ParseArrayContains(node, negate));
}
else
{
var parmName = this.ExtractPath(node.Object, false);
object parmValue = this.ExtractValue(node.Arguments[0]);
this.AddCondition(parmName, (negate ? "!" : "~") + parmValue.ToString());
return(null);
}
}
case "StartsWith":
{
var parmName = this.ExtractPath(node.Object, false);
object parmValue = this.ExtractValue(node.Arguments[0]);
this.AddCondition(parmName, (negate ? "!" : "^") + parmValue.ToString());
return(null);
}
case "Any":
{
var parmName = this.ExtractPath(node.Arguments[0], false);
// Process lambda
var result = new List <KeyValuePair <string, object> >();
var subQueryExpressionVisitor = new HttpQueryExpressionVisitor(result, node.Arguments[0].Type);
if (node.Arguments.Count == 2)
{
subQueryExpressionVisitor.Visit(node.Arguments[1]);
// Result
foreach (var itm in result)
{
this.AddCondition(String.Format("{0}.{1}", parmName, itm.Key), negate ? $"!{itm.Value}" : itm.Value);
}
return(null);
}
else
{
return(null);
}
}
default: // extended fn?
{
var extendedFn = QueryFilterExtensions.GetExtendedFilterByMethod(node.Method);
if (extendedFn == null)
{
throw new MissingMemberException($"Cannot find extension method {node.Method}");
}
if (extendedFn.ExtensionMethod.ReturnType == typeof(bool))
{
var parmName = this.ExtractPath(node.Arguments[0], false);
if (parmName == null && typeof(IdentifiedData).IsAssignableFrom(node.Arguments[0].Type))
{
parmName = "id";
}
else if (parmName == null)
{
throw new InvalidOperationException($"Cannot determine how to map {extendedFn.Name}");
}
var callValue = $"{(negate ? "!" : "")}:({extendedFn.Name}";
if (node.Arguments.Count > 1)
{
callValue += $"|{String.Join(",", node.Arguments.Skip(1).Select(o => this.PrepareValue(this.ExtractValue(o), true)))}";
}
callValue += ")";
this.AddCondition(parmName, callValue);
return(node);
}
return(null);
}
}
}
