Add project files.

2018-02-11 19:55:29 -06:00
parent f51b9350e4
commit 50fc50225d
23 changed files with 988 additions and 0 deletions
@@ -0,0 +1,107 @@
+using PoweredSoft.DynamicLinq.Helpers;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace PoweredSoft.DynamicLinq.Fluent
+{
+    public class QueryBuilder<T>
+    {
+        public IQueryable<T> Query { get; set; }
+
+        public Type QueryableType { get; set; }
+
+        public List<QueryFilterPart> Parts { get; protected set; } = new List<QueryFilterPart>();
+
+        public QueryBuilder(IQueryable<T> query)
+        {
+            Query = query;
+        }
+
+        public QueryBuilder<T> Compare(string path, ConditionOperators conditionOperators, object value, 
+            bool convertConstantToLeftOperator = true, bool and = true)
+        {
+            Parts.Add(new QueryFilterPart
+            {
+                And = and,
+                ConditionOperator = conditionOperators,
+                Path = path,
+                Value = value,
+                ConvertConstantToLeftOperator = convertConstantToLeftOperator
+            });
+
+            return this;
+        }
+
+        public QueryBuilder<T> SubQuery(Action<QueryBuilder<T>> subQuery, bool and = true)
+        {
+            // create query builder for same type.
+            var qb = new QueryBuilder<T>(Query);
+
+            // callback.
+            subQuery(qb);
+            
+            // create a query part.
+            var part = new QueryFilterPart();
+            part.And = and;
+            part.Parts = qb.Parts;
+            Parts.Add(part);
+            
+            //return self.
+            return this;
+        }
+
+        public QueryBuilder<T> And(string path, ConditionOperators conditionOperator, object value, bool convertConstantToLeftOperator = true)
+            => Compare(path, conditionOperator, value, convertConstantToLeftOperator: convertConstantToLeftOperator, and: true);
+
+        public QueryBuilder<T> Or(string path, ConditionOperators conditionOperator, object value, bool convertConstantToLeftOperator = true)
+            => Compare(path, conditionOperator, value, convertConstantToLeftOperator: convertConstantToLeftOperator, and: false);
+
+        public QueryBuilder<T> And(Action<QueryBuilder<T>> subQuery)
+            => SubQuery(subQuery, true);
+
+        public QueryBuilder<T> Or(Action<QueryBuilder<T>> subQuery)
+            => SubQuery(subQuery, false);
+
+        public IQueryable<T> Build()
+        {
+            var parameter = Expression.Parameter(typeof(T), "t");
+            var expression = BuildExpression(parameter, Parts);
+            var lambda = Expression.Lambda<Func<T, bool>>(expression, parameter);
+            var query = Query.Where(lambda);
+            return query;
+        }
+
+        protected Expression BuildExpression(ParameterExpression parameter, List<QueryFilterPart> parts)
+        {
+            Expression ret = null;
+
+            parts.ForEach(part =>
+            {
+                Expression innerExpression;
+                if (part.Parts?.Any() == true)
+                    innerExpression = BuildExpression(parameter, part.Parts);
+                else
+                    innerExpression = BuildExpression(parameter, part);
+
+                if (ret != null)
+                    ret = part.And ? Expression.And(ret, innerExpression) : Expression.Or(ret, innerExpression);
+                else
+                    ret = innerExpression;
+            });
+
+            return ret;
+        }
+
+        private Expression BuildExpression(ParameterExpression parameter, QueryFilterPart part)
+        {
+            var member = QueryableHelpers.ResolvePathForExpression(parameter, part.Path);
+            var constant = part.ConvertConstantToLeftOperator ? QueryableHelpers.GetConstantSameAsLeftOperator(member, part.Value) : Expression.Constant(part.Value);
+            var expression = QueryableHelpers.GetConditionExpressionForMember(parameter, member, part.ConditionOperator, constant);
+            return expression;
+        }
+    }
+}
@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace PoweredSoft.DynamicLinq.Fluent
+{
+    public class QueryFilterPart
+    {
+        public string Path { get; set; }
+        public ConditionOperators ConditionOperator { get; set; }
+        public object Value { get; set; }
+        public bool And { get; set; }
+        public bool ConvertConstantToLeftOperator { get; set; }
+
+        public List<QueryFilterPart> Parts { get; set; } = new List<QueryFilterPart>();
+    }
+}