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Dapper-将类名称/属性映射到数据库字段

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我上课... 

public class WireTransferRequest
    {
        public int RequestID { get; set; }
        public DateTime RequestDate { get; set; }
        public string RequesterName { get; set; }
        public string AuthorizerName { get; set; }
        public string AuthorizerSignature { get; set; }
        public DateTime TransferDate { get; set; }
        public string CustomerNames { get; set; }
        public string Reasons { get; set; }
        public string Amounts { get; set; }
        public decimal TotalOfAmounts { get; set; }
    }

我有一张桌子。...

CREATE TABLE IF NOT EXISTS `digital_forms`.`wire_transfer_request` (
  `request_id` INT NOT NULL,`request_date` DATETIME NOT NULL,`requester_name` VARCHAR(64) NOT NULL,`authorizer_name` VARCHAR(64) NULL,`authorizer_signature` VARCHAR(64) NULL,`transfer_date` DATETIME NULL,`customer_names` VARCHAR(64) NULL,`customer_reasons` VARCHAR(128) NULL,`customer_amounts` VARCHAR(128) NULL,`total_of_customer_amounts` DECIMAL(19,2) NULL,PRIMARY KEY (`request_id`),INDEX `idx_request_date` (`request_date` ASC) VISIBLE,INDEX `idx_requestor_name` (`requestor_name` ASC) VISIBLE)
ENGINE = InnoDB

我有一个查询... 

    public override void Add(WireTransferRequest request)
        {

            if (request == null)
                throw new ArgumentNullException(nameof(request));

            request.RequestID = _transaction.Connection.ExecuteScalar<int>(

            "INSERT INTO wire_transfer_request(request_date,requester_name,authorizer_name," +
                                             "authorizer_signature,transfer_date,customer_names," +
                                             "customer_reasons,customer_amounts,total_of_customer_amounts" +

            "VALUES (@request_date,@requester_name,@authorizer_name," +
                                             "@authorizer_signature,@transfer_date,@customer_names," +
                                             "@customer_reasons,@customer_amounts,@total_of_customer_amounts; SELECT SCOPE_IDENTITY()",new
                                             {
                                                 request_date = request.RequestDate,requester_name = request.RequesterName,authorizer_name = request.AuthorizerName,authorizer_signature = request.AuthorizerSignature,transfer_date = request.TransferDate,customer_names = request.CustomerNames,customer_reasons = request.Reasons,customer_amounts = request.Amounts,total_of_customer_amounts = request.TotalOfAmounts,},_transaction
                                             );
        }

我希望Dapper能够正确识别和映射列名和表名。 Google对此进行了快速搜索，发现了很多旧的结果，因此，我很想知道更新的（如果可能的话）解决方案/解决方法。

我尝试使用MatchNamesWithUnderscores映射器，但无法达到我期望的插入效果。

nmwangyu 回答：Dapper-将类名称/属性映射到数据库字段

我不是Dapper专家，但这是我的想法。

选项0。有效

您的sql中缺少2个)。

以下代码段有效。

var sql = "INSERT INTO wire_transfer_request(request_date,requester_name,authorizer_name," +
         "authorizer_signature,transfer_date,customer_names," +
         "customer_reasons,customer_amounts,total_of_customer_amounts)" +

"VALUES (@request_date,@requester_name,@authorizer_name," +
         "@authorizer_signature,@transfer_date,@customer_names," +
         "@customer_reasons,@customer_amounts,@total_of_customer_amounts); SELECT SCOPE_IDENTITY()";

var o = new 
{
    request_date = DateTime.UtcNow,requester_name = "X",authorizer_name = "Y",authorizer_signature = "Sig",transfer_date = DateTime.UtcNow,customer_names = "Z",customer_reasons = "A",customer_amounts = "B",total_of_customer_amounts = 10m,};

var inserted = conn.ExecuteScalar(sql,o);

inserted包含新插入的行的request_id。

选项1。表的类

Insert（不是此答案的核心）来自官方Dapper.Contrib。

[Table("wire_transfer_request")]
public class WireTransferRequest2
{
    public int request_id { get; set; }

    public DateTime request_date { get; set; }

    public string requester_name { get; set; }

    public string authorizer_name { get; set; }

    public string authorizer_signature { get; set; }

    public DateTime transfer_date { get; set; }

    public string customer_names { get; set; }

    public string customer_reasons { get; set; }

    public string customer_amounts { get; set; }

    public decimal total_of_customer_amounts { get; set; }
}

using Dapper.Contrib.Extensions;

(...)

var o = new WireTransferRequest2
{
    request_id = 1,request_date = DateTime.UtcNow,};

conn.Insert(o);

选项2。使用ColumnAttribute

Manually map column names with class properties上的详细信息。

asp.netc#dapper
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