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我正在开发使用 Dapper 作为 DAL 层的项目，因为我们仍在使用内联查询。为了构建我们的查询，我们使用了 dapper sqlBuilder 模板。

下面是我们的方法代码之一：

SqlBuilder builder = new SqlBuilder();
        var update = builder.AddTemplate("DECLARE @transactionID bigint; " +
                                         "EXEC @transactionID = dbo.sp_getAndIncrementTransactionCounter @accountID; " +
                                         "UPDATE TimeEntryIndex /**set**/ OUTPUT inserted.id /**where**/");

        builder.Set("userID         = @userID", new { field.UserId });
        builder.Set("deviceID       = @deviceID", new { field.DeviceId });
        builder.Set("deviceName     = @deviceName", new { field.DeviceName });
        builder.Set("transactionID  = @transactionID");
        builder.Set("state          = @state", new { ttContent.state });
        builder.Set("lastUpdated    = GETUTCDATE()");

        // Determine which fields to update
        if (!string.IsNullOrEmpty(ttContent.title))
        {
            builder.Set("title = @title", new { ttContent.title });
        }
        if (!string.IsNullOrEmpty(ttContent.description))
        {
            builder.Set("description = @description", new { ttContent.description });
        }
        if (tEntryIndex.finish.HasValue)
        {
            builder.Set("finish = @finish", new { tEntryIndex.finish });
        }
        if (ttContent.created.HasValue)
        {
            builder.Set("created = @created", new { ttContent.created });
        }
        if (tEntryIndex.duration.HasValue)
        {
            builder.Set("duration = @duration", new { tEntryIndex.duration });
        }

        builder.Where("accountid = @accountid", new { accountid = field.AccountId });
        builder.Where("id = @id", new { id = timeEntryId });

        var result = new Result<long?>(sqlConn.ExecuteScalar<long?>(update.RawSql, update.Parameters));

在上面的代码中，它看起来是正确的数据库中的少量字段。但是，当我们在表中有很多字段时，比如说 25 列，仅用于构建该构建器就需要大量工作。

我想用反射将它包装在一个函数中。我首先尝试这样的事情：

foreach (PropertyInfo prop in typeof(Account).GetProperties())
{
   // Will do checking on every type possible
   if (typeof(String).IsAssignableFrom(prop.PropertyType) && prop.GetValue(aContent) != null && !string.IsNullOrEmpty(prop.GetValue(aContent).ToString()))
   {
       builder.Set(string.Format("{0} = @{0}", prop.Name.ToLowerInvariant()), new { <what should I put in here> });
   }
 }

问题是我找不到一种方法让它与 Dapper 在其构建器类上需要的动态参数一起工作。

每一个建议和帮助将不胜感激。

4

1 回答 1

0

您可以使用DynamicParamtersClass 来添加动态名称-值对：

var prms = new DynamicParameters();
foreach (PropertyInfo prop in typeof(Account).GetProperties())
{
    // Will do checking on every type possible
    if (typeof(String).IsAssignableFrom(prop.PropertyType) && prop.GetValue(aContent) != null && !string.IsNullOrEmpty(prop.GetValue(aContent).ToString()))
    {
        builder.Set(string.Format("{0} = @{0}", prop.Name.ToLowerInvariant())ף
        prms.Add(prop.Name.ToLowerInvariant(), prop.GetValue(aContent));
    }
}

prms.AddDynamicParams(update.Parameters);
var result = new Result<long?>(sqlConn.ExecuteScalar<long?>(update.RawSql, prms));
于 2021-09-12T15:01:25.433 回答