/* 创建者：菜刀居士的博客

 * 创建日期：2014年07月06号

 */

namespace Net.CRM.OrganizationService

{

    using System;

    using Microsoft.Xrm.Sdk;

    using Microsoft.Xrm.Sdk.Query;

    using System.Collections.Generic;

    /// <summary>

    /// QueryExpression

    /// </summary>

    public class QueryExpressionDemo

    {

        /// <summary>

        /// 基本模式，构造查询--QueryExpression

        /// </summary>

        public void CreateQueryExpression()

        {

            QueryExpression query = new QueryExpression();

            //查询的实体名称

            query.EntityName = "new_accountproduct";

            //查询实体的属性集合

            query.ColumnSet = new ColumnSet("new_product","new_name","new_price");

            //查询条件

            query.Criteria.AddCondition(new ConditionExpression("statecode",ConditionOperator.Equal,0));

            query.Criteria.AddCondition(new ConditionExpression("new_name", ConditionOperator.Like, "水果" + "%"));

            List<Guid> list = new List<Guid>();

            list.Add(new Guid("27BB1B31-09BB-E311-B590-D89D671782D3"));

            list.Add(new Guid("E8F8D412-31BB-E311-B590-D89D671782D3"));

            query.Criteria.AddCondition(new ConditionExpression("new_product",ConditionOperator.In,list.ToArray()));

            query.Criteria.AddCondition(new ConditionExpression("new_name", ConditionOperator.NotNull));

            query.Criteria.AddCondition(new ConditionExpression("new_price", ConditionOperator.Null));

        }

        /// <summary>

        /// 高速模式，构造查询--QueryExpression

        /// </summary>

        public void CreateQuickQueryExpression()

        {

            QueryExpression query = "new_accountproduct".ToQuery("new_product", "new_name", "new_price");

            query.AddEqual("statecode", 0);

            query.AddLike("new_name", "水果" + "%");

            List<Guid> list = new List<Guid>();

            list.Add(new Guid("27BB1B31-09BB-E311-B590-D89D671782D3"));

            list.Add(new Guid("E8F8D412-31BB-E311-B590-D89D671782D3"));

            query.AddIn("new_product", list.ToArray());

            query.AddNotNull("new_name");

            query.AddNull("new_price");

        }

    }

    public static class ExtensionFunction

    {

        public static QueryExpression ToQuery(this string entityName)

        {

            QueryExpression query = new QueryExpression();

            query.EntityName = entityName;

            return query;

        }

        public static QueryExpression ToQuery(this string entityName,params string[] Attrs)

        {

            QueryExpression query = new QueryExpression();

            query.EntityName = entityName;

            query.ColumnSet = new ColumnSet(Attrs);

            return query;

        }

        public static void AddEqual<T>(this QueryExpression query,string name,T value)

        {

            query.Criteria.AddCondition(new ConditionExpression(name,ConditionOperator.Equal,value));

        }

        public static void AddLike(this QueryExpression query, string name,string value)

        {

            query.Criteria.AddCondition(new ConditionExpression(name,ConditionOperator.Like,value));

        }

        public static void AddIn<T>(this QueryExpression query, string name,T[] values)

        {

            query.Criteria.AddCondition(new ConditionExpression(name, ConditionOperator.In, values));

        }

        public static void AddNotNull(this QueryExpression query,params string[] attrs)

        {

            if (attrs != null && attrs.Length > 0)

            {

                foreach(string name in attrs)

                {

                    query.Criteria.AddCondition(new ConditionExpression(name, ConditionOperator.NotNull));

                }

            }

        }

        public static void AddNull(this QueryExpression query, params string[] attrs)

        {

            if (attrs != null && attrs.Length > 0)

            {

                foreach (string name in attrs)

                {

                    query.Criteria.AddCondition(new ConditionExpression(name, ConditionOperator.Null));

                }

            }

        }

    }

}

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