c# - 使用 Dapper 映射 SqlGeography

Question

我有实体“点”，其中包含 ID、文本和地理坐标。

CREATE TABLE [Point] (
    [Id] INT IDENTITY CONSTRAINT [PK_Point_Id] PRIMARY KEY,
    [Coords] GEOGRAPHY NOT NULL,
    [Text] NVARCHAR(32) NOT NULL,
    [CreationDate] DATETIME NOT NULL,
    [IsDeleted] BIT NOT NULL DEFAULT(0)
)

CREATE PROCEDURE [InsertPoint]
    @text NVARCHAR(MAX),
    @coords GEOGRAPHY
AS BEGIN
    INSERT INTO [Point](Text, Coords, CreationDate)
    VALUES(@text, @coords, GETUTCDATE())    
    SELECT * FROM [Point] WHERE [Id] = SCOPE_IDENTITY()
END

这是插入表和存储过程的ts sql代码。我有使用 dapper 的类(class):

public class DapperRequester : IDisposable {
    private readonly SqlConnection _connection;
    private SqlTransaction _transaction;

    public DapperRequester(string connectionString) {
        _connection = new SqlConnection(connectionString);
        _connection.Open();
    }
    public void Dispose() {
        _connection.Close();
    }

    public void BeginTransaction() {
        _transaction = _connection.BeginTransaction();
    }
    public void CommitTransaction() {
        _transaction.Commit();
    }
    public void RollbackTransaction() {
        _transaction.Rollback();
    }

    public void Query(string query, object parameters = null) {
        Dapper.SqlMapper.Execute(_connection, query, parameters, transaction: _transaction);
    }

    public void QueryProc(string procName, object parameters = null) {
        Dapper.SqlMapper.Execute(_connection, procName, parameters, commandType: CommandType.StoredProcedure, transaction: _transaction);
    }

    public IEnumerable<T> Execute<T>(string query, object parameters = null) {
        return Dapper.SqlMapper.Query<T>(_connection, query, parameters, transaction: _transaction);
    }

    public IEnumerable<dynamic> ExecuteProc(string procName, object parameters = null) {
        return Dapper.SqlMapper.Query(_connection, procName, parameters,
                                         commandType: CommandType.StoredProcedure, transaction: _transaction);
    }

    public IEnumerable<T> ExecuteProc<T>(string procName, object parameters = null) {
        return Dapper.SqlMapper.Query<T>(_connection, procName, parameters,
                                         commandType: CommandType.StoredProcedure, transaction: _transaction);
    }
}

c#类是:

public class Point
{
    public int Id { get; set; }
    public SqlGeography Coords { get; set; }
    public string Text { get; set; }
}

存储库有方法

public Point InsertPoint(string text, SqlGeography coords)
    {
        using (var requester = GetRequester())
        {
            return requester.ExecuteProc<Point>("InsertPoint", new { text, coords }).FirstOrDefault();
        }
    }

当我将这样的系统用于任何其他类时，一切正常，但映射有问题，我认为这是因为 SqlGeography 类型。使用:

SqlGeography coords = new SqlGeography();
        coords = SqlGeography.Point(10.5, 15.5, 4326);
        Point point = new Point { Coords = coords, Text = "Text" };
        point = Repositories.PointRepository.InsertPoint(point.Text, point.Coords);

而且我有一个异常Microsoft.SqlServer.Types.SqlGeography 类型的成员坐标不能用作参数值

映射那种类型有什么 secret 吗？

Answer 1

Dapper 1.32 现在 includes direct support for this .您的代码现在应该可以正常工作了。