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【免费下载链接】Dapper项目地址: https://gitcode.com/gh_mirrors/dapper3/Dapper
还在为传统ORM的性能瓶颈而烦恼?想要找到既简单又高效的数据访问解决方案?Dapper作为Stack Overflow团队开发的开源项目,正是你寻找的答案。这款轻量级ORM工具通过扩展ADO.NET连接,让数据库操作变得异常简单而强大。
Dapper的核心优势在于其极简设计和卓越性能。与传统ORM相比,它避免了复杂的映射配置和额外的性能开销,同时保留了SQL的灵活性和控制力。
Dapper的三大核心价值:
通过NuGet包管理器安装Dapper:
Install-Package Dapper或者使用强名称版本:
Install-Package Dapper.StrongName体验Dapper的简洁查询语法:
using (var connection = new SqlConnection(connectionString)) { var users = connection.Query<User>("SELECT * FROM Users WHERE IsActive = @IsActive", new { IsActive = true }); }Dapper自动处理参数化查询,确保安全性和性能:
// 匿名对象传参 var user = connection.QueryFirstOrDefault<User>( "SELECT * FROM Users WHERE Id = @Id AND Email = @Email", new { Id = 1, Email = "user@example.com" });轻松处理复杂的数据关系:
var query = @" SELECT p.*, u.* FROM Products p INNER JOIN Users u ON p.CreatedBy = u.Id WHERE p.CategoryId = @CategoryId"; var products = connection.Query<Product, User, Product>( query, (product, user) => { product.Creator = user; return product; }, new { CategoryId = 5 }, splitOn: "Id");简化数据库事务操作:
using (var transaction = connection.BeginTransaction()) { try { connection.Execute("INSERT INTO Orders (...) VALUES (...)", order, transaction); connection.Execute("INSERT INTO OrderItems (...) VALUES (...)", orderItems, transaction); transaction.Commit(); } catch { transaction.Rollback(); throw; } }Dapper内置智能缓存机制:
// 清理查询缓存以释放内存 SqlMapper.PurgeQueryCache();针对大批量数据操作:
var products = new List<Product> { new Product { Name = "Product 1", Price = 10.99m }, new Product { Name = "Product 2", Price = 15.50m } }; connection.Execute("INSERT INTO Products (Name, Price) VALUES (@Name, @Price)", products);使用SqlBuilder灵活构建查询条件:
var builder = new SqlBuilder(); var template = builder.AddTemplate("SELECT * FROM Products /**where**/"); if (!string.IsNullOrEmpty(searchTerm)) { builder.Where("Name LIKE @SearchTerm", new { SearchTerm = $"%{searchTerm}%" }); } var results = connection.Query<Product>(template.RawSql, template.Parameters);轻松集成现有存储过程:
var parameters = new DynamicParameters(); parameters.Add("@UserId", 123); parameters.Add("@TotalOrders", dbType: DbType.Int32, direction: ParameterDirection.Output); connection.Execute("GetUserOrderStats", parameters, commandType: CommandType.StoredProcedure); var totalOrders = parameters.Get<int>("@TotalOrders");| 技术方案 | 平均响应时间 | 内存占用 |
|---|---|---|
| Dapper | 135.2 µs | 11.6 KB |
| Entity Framework Core | 268.9 µs | 7.5 KB |
| NHibernate | 279.1 µs | 29.8 KB |
从数据可见,Dapper在响应时间和资源消耗方面都表现出色,特别适合对性能要求较高的应用场景。
Dapper以其简洁的设计和卓越的性能,为.NET开发者提供了理想的数据访问解决方案。立即开始使用,体验高效数据操作的魅力!
【免费下载链接】Dapper项目地址: https://gitcode.com/gh_mirrors/dapper3/Dapper
创作声明:本文部分内容由AI辅助生成(AIGC),仅供参考