private Query VisitExpression(Expression expr, string prefix = null)
{
// Single: x.Active
if (expr is MemberExpression && expr.Type == typeof(bool))
{
return(Query.EQ(this.GetField(expr, prefix), new BsonValue(true)));
}
// Not: !x.Active or !(x.Id == 1)
else if (expr.NodeType == ExpressionType.Not)
{
var unary = expr as UnaryExpression;
return(Query.Not(this.VisitExpression(unary.Operand, prefix)));
}
// Equals: x.Id == 1
else if (expr.NodeType == ExpressionType.Equal)
{
var bin = expr as BinaryExpression;
return(new QueryEquals(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// NotEquals: x.Id != 1
else if (expr.NodeType == ExpressionType.NotEqual)
{
var bin = expr as BinaryExpression;
return(Query.Not(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// LessThan: x.Id < 5
else if (expr.NodeType == ExpressionType.LessThan)
{
var bin = expr as BinaryExpression;
return(Query.LT(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// LessThanOrEqual: x.Id <= 5
else if (expr.NodeType == ExpressionType.LessThanOrEqual)
{
var bin = expr as BinaryExpression;
return(Query.LTE(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// GreaterThan: x.Id > 5
else if (expr.NodeType == ExpressionType.GreaterThan)
{
var bin = expr as BinaryExpression;
return(Query.GT(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// GreaterThanOrEqual: x.Id >= 5
else if (expr.NodeType == ExpressionType.GreaterThanOrEqual)
{
var bin = expr as BinaryExpression;
return(Query.GTE(this.GetField(bin.Left, prefix), this.VisitValue(bin.Right, bin.Left)));
}
// And: x.Id > 1 && x.Name == "John"
else if (expr.NodeType == ExpressionType.AndAlso)
{
var bin = expr as BinaryExpression;
var left = this.VisitExpression(bin.Left, prefix);
var right = this.VisitExpression(bin.Right, prefix);
return(Query.And(left, right));
}
// Or: x.Id == 1 || x.Name == "John"
else if (expr.NodeType == ExpressionType.OrElse)
{
var bin = expr as BinaryExpression;
var left = this.VisitExpression(bin.Left);
var right = this.VisitExpression(bin.Right);
return(Query.Or(left, right));
}
// Constant: do nothing (at this point it's useful only to PredicateBuilder)
else if (expr.NodeType == ExpressionType.Constant)
{
var constant = expr as ConstantExpression;
if (constant.Value is bool)
{
var value = (bool)constant.Value;
return(value ? Query.All() : new QueryEmpty());
}
}
// Invoke: call inner Lambda expression (used in PredicateBuilder)
else if (expr.NodeType == ExpressionType.Invoke)
{
var invocation = expr as InvocationExpression;
var lambda = invocation.Expression as LambdaExpression;
return(this.VisitExpression(lambda.Body));
}
// MethodCall: x.Name.StartsWith("John")
else if (expr is MethodCallExpression)
{
var met = expr as MethodCallExpression;
var method = met.Method.Name;
#if NET35
var type = met.Method.ReflectedType;
#else
var type = met.Method.DeclaringType;
#endif
var paramType = met.Arguments[0] is MemberExpression ?
(ExpressionType?)(met.Arguments[0] as MemberExpression).Expression.NodeType :
null;
// StartsWith
if (method == "StartsWith")
{
var value = this.VisitValue(met.Arguments[0], null);
return(Query.StartsWith(this.GetField(met.Object, prefix), value));
}
// Equals
else if (method == "Equals")
{
var value = this.VisitValue(met.Arguments[0], null);
return(Query.EQ(this.GetField(met.Object, prefix), value));
}
// Contains (String): x.Name.Contains("auricio")
else if (method == "Contains" && type == typeof(string))
{
var value = this.VisitValue(met.Arguments[0], null);
return(Query.Contains(this.GetField(met.Object, prefix), value));
}
// Contains (Enumerable): x.ListNumber.Contains(2)
else if (method == "Contains" && type == typeof(Enumerable))
{
var field = this.GetField(met.Arguments[0], prefix);
var value = this.VisitValue(met.Arguments[1], null);
return(Query.EQ(field, value));
}
// Any (Enumerable): x.Customer.Any(z => z.Name.StartsWith("John"))
else if (method == "Any" && type == typeof(Enumerable) && paramType == ExpressionType.Parameter)
{
var field = this.GetField(met.Arguments[0]);
var lambda = met.Arguments[1] as LambdaExpression;
return(this.VisitExpression(lambda.Body, field + "."));
}
// System.Linq.Enumerable methods (constant list items)
else if (type == typeof(Enumerable))
{
return(ParseEnumerableExpression(met));
}
}
throw new NotImplementedException("Not implemented Linq expression");
}
private Query VisitExpression(Expression expr)
{
if (expr.NodeType == ExpressionType.Equal) // ==
{
var bin = expr as BinaryExpression;
return(new QueryEquals(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr is MemberExpression && expr.Type == typeof(bool)) // x.Active
{
return(Query.EQ(this.VisitMember(expr), new BsonValue(true)));
}
else if (expr.NodeType == ExpressionType.NotEqual) // !=
{
var bin = expr as BinaryExpression;
return(Query.Not(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr.NodeType == ExpressionType.Not) // !x.Active
{
var bin = expr as UnaryExpression;
return(Query.EQ(this.VisitMember(bin), new BsonValue(false)));
}
else if (expr.NodeType == ExpressionType.LessThan) // <
{
var bin = expr as BinaryExpression;
return(Query.LT(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr.NodeType == ExpressionType.LessThanOrEqual) // <=
{
var bin = expr as BinaryExpression;
return(Query.LTE(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr.NodeType == ExpressionType.GreaterThan) // >
{
var bin = expr as BinaryExpression;
return(Query.GT(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr.NodeType == ExpressionType.GreaterThanOrEqual) // >=
{
var bin = expr as BinaryExpression;
return(Query.GTE(this.VisitMember(bin.Left), this.VisitValue(bin.Right)));
}
else if (expr is MethodCallExpression)
{
var met = expr as MethodCallExpression;
var method = met.Method.Name;
// StartsWith
if (method == "StartsWith")
{
var value = this.VisitValue(met.Arguments[0]);
return(Query.StartsWith(this.VisitMember(met.Object), value));
}
// Contains
else if (method == "Contains")
{
var value = this.VisitValue(met.Arguments[0]);
return(Query.Contains(this.VisitMember(met.Object), value));
}
// Equals
else if (method == "Equals")
{
var value = this.VisitValue(met.Arguments[0]);
return(Query.EQ(this.VisitMember(met.Object), value));
}
}
else if (expr is BinaryExpression && expr.NodeType == ExpressionType.AndAlso)
{
// AND
var bin = expr as BinaryExpression;
var left = this.VisitExpression(bin.Left);
var right = this.VisitExpression(bin.Right);
return(Query.And(left, right));
}
else if (expr is BinaryExpression && expr.NodeType == ExpressionType.OrElse)
{
// OR
var bin = expr as BinaryExpression;
var left = this.VisitExpression(bin.Left);
var right = this.VisitExpression(bin.Right);
return(Query.Or(left, right));
}
throw new NotImplementedException("Not implemented Linq expression");
}
private QueryBuilder convertQuery(string _field, string _operator, string _value)
{
_operator = _operator.ToLower();
bool _ok = false;
Query _query = null;
string _msg = string.Empty;
switch (_operator)
{
case "all": //int order = Ascending)
//_query = Query.All();
break;
case "all_field": //string field, int order = Ascending)
//_query = Query.All();
break;
case "eq": //string field, BsonValue value)
if (_value.IsNumeric())
{
if (_value.IndexOf('.') != -1)
{
double _d = 0;
if (double.TryParse(_value, out _d))
{
_ok = true;
_query = Query.EQ(_field, new BsonValue(_d));
}
}
else
{
int _val = 0;
if (int.TryParse(_value, out _val))
{
_ok = true;
_query = Query.EQ(_field, new BsonValue(_val));
}
}
}
else
{
_ok = true;
_query = Query.EQ(_field, new BsonValue(_value));
}
break;
case "lt": //string field, BsonValue value)
_value = _value.Trim();
if (_value.IsNumeric())
{
_ok = true;
_query = Query.LT(_field, new BsonValue(_value));
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not number: [" + _value + "]";
}
break;
case "lte": //string field, BsonValue value)
_value = _value.Trim();
if (_value.IsNumeric())
{
_ok = true;
_query = Query.LTE(_field, new BsonValue(_value));
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not number: [" + _value + "]";
}
break;
case "gt": //string field, BsonValue value)
_value = _value.Trim();
if (_value.IsNumeric())
{
_ok = true;
_query = Query.GT(_field, new BsonValue(_value));
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not number: [" + _value + "]";
}
break;
case "gte": //string field, BsonValue value)
_value = _value.Trim();
if (_value.IsNumeric())
{
_ok = true;
_query = Query.GTE(_field, new BsonValue(_value));
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not number: [" + _value + "]";
}
break;
case "between": //string field, BsonValue start, BsonValue end, bool startEquals = true, bool endEquals = true)
string[] a = _value.Split('|');
if (a.Length == 2)
{
string v1 = a[0].Trim(), v2 = a[1].Trim();
if (v1.IsNumeric() && v2.IsNumeric())
{
_ok = true;
_query = Query.Between(_field, new BsonValue(v1), new BsonValue(v2));
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not number: [" + _value + "]";
}
}
else
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not format: [ number_start | number_end ]";
}
break;
case "start_with": //string field, string value)
_ok = true;
_query = Query.StartsWith(_field, _value);
break;
case "contains": //string field, string value)
_ok = true;
_query = Query.Contains(_field, _value);
break;
case "not": //string field, BsonValue value)
_ok = true;
_query = Query.Not(_field, new BsonValue(_value));
break;
//case "not_query": //Query query, int order = Query.Ascending)
// _query = Query.All();
// break;
//case "in_bson_array": //string field, BsonArray value)
// _query = Query.All();
// break;
case "in_array": //string field, params BsonValue[] values)
_value = _value.Trim();
if (string.IsNullOrEmpty(_value))
{
_msg = "The field [" + _field + "] using operator [" + _operator + "] to compare value be not format: [ number_start | number_end ]";
}
else
{
_ok = true;
BsonValue[] a_in_array = _value.Split('|').Select(x => new BsonValue(x)).ToArray();
_query = Query.In(_field, a_in_array);
}
break;
//case "in_ienumerable": //string field, IEnumerable<BsonValue> values)
// _query = Query.All();
// break;
}
return(new QueryBuilder()
{
Ok = _ok, Query = _query, Msg = _msg
});
}
