Elastic Search.NET -NEST使用（1）

Elastic Search.NET -NEST

Object Initializer 语法去构造查询

Match All query

最简单的查询应该就是 match_all 了，这种查询会返回所有的文档，并给每份文档的 _score 统一赋值为 1.0

匹配的文档并不是都会在一次响应中全部返回，默认情况下只返回前十份。你可以使用 from 和 size 来将结果分页

var searchResponse = client.Search<Project>(s => s
    .Query(q => q
        .MatchAll()
    )
);

上面使用 Fluent API 来描述查询。

NEST 还公开了一种 Object Initializer 语法去构造查询

var searchRequest = new SearchRequest<Project>
{
    Query = new MatchAllQuery()
};

searchResponse = client.Search<Project>(searchRequest);

Search request parameters

search request 有一些可用的参数，你可以参阅 search 以获得详细的信息。

以下是一个示例：

            var searchRequest = new SearchRequest<Tmx2ESModel>();
            searchRequest.From = page;
            searchRequest.Size = size;
            var list = new List<QueryContainer>();
            //optional
            if (!string.IsNullOrWhiteSpace(inModel.ClientGuid))
            {
            	//精准查询使用keyword
                var clientGuid = new MatchQuery() { Field = Infer.Field<Tmx2ESModel>(f => f.ClientGuid.Suffix("keyword")), Query = inModel.ClientGuid };
                list.Add(clientGuid);
            }
             searchRequest.Query = new BoolQuery() { Must = list };

            var searchResponse = ESClient.Client.SearchAsync<Tmx2ESModel>(searchRequest);

在net core 注册ES

添加ESSever

/// <summary>
    /// 访问ElasticSearch服务类
    /// </summary>
    public class ESSever : IESSever
    {
        /// <summary>
        /// Linq查询的官方Client
        /// </summary>
        public IElasticClient ElasticLinqClient { get; set; }
        /// <summary>
        /// Js查询的官方Client
        /// </summary>
        public IElasticLowLevelClient ElasticJsonClient { get; set; }
        public ESSever(IConfiguration configuration)
        {
            var uris = configuration["ElasticSearchContext:ESUri"].Split(",").ToList().ConvertAll(x => new Uri(x));
            var connectionPool = new StaticConnectionPool(uris);//配置请求池
            var settings = new ConnectionSettings(connectionPool).RequestTimeout(TimeSpan.FromSeconds(30));//请求配置参数
            settings.DisableDirectStreaming().DefaultIndex(configuration["ElasticSearchContext:ESIndexName"]);
            this.ElasticJsonClient = new ElasticLowLevelClient(settings);//json请求客户端初始化
            this.ElasticLinqClient = new ElasticClient(settings);//linq请求客户端初始化
        }

        /// <summary>
        /// Creates the Tmx2ESModel asynchronous.
        /// </summary>
        /// <param name="model">The model.</param>
        /// <returns></returns>
        public Task<Nest.CreateResponse> CreateAsync(Tmx2ESModel model)
        {
            return ElasticLinqClient.CreateDocumentAsync(model);
        }
    }

在startup里面在ConfigureServices下面添加如下代码即可

services.AddSingleton<IESSever, ESSever>();

参考：

【三】在Asp.Netcore上使用ElasticSearch