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关于Dapper的使用笔记1
********************************************************************1、Execute a query and map the results to a strongly typed ListNote: all extension methods assume the connection is already open, they will fail if the connection is closed.public static IEnumerable<T> Query<T>(this IDbConnection cnn, string sql, object param = null, SqlTransaction transaction = null, bool buffered = true)Example usage:
public class Dog{ public int? Age { get; set; } public Guid Id { get; set; } public string Name { get; set; } public float? Weight { get; set; } public int IgnoredProperty { get { return 1; } }} var guid = Guid.NewGuid();var dog = connection.Query<Dog>("select Age = @Age, Id = @Id", new { Age = (int?)null, Id = guid }); dog.Count().IsEqualTo(1);dog.First().Age.IsNull();dog.First().Id.IsEqualTo(guid);
********************************************************************2、Execute a query and map it to a list of dynamic objects
public static IEnumerable<dynamic> Query (this IDbConnection cnn, string sql, object param = null, SqlTransaction transaction = null, bool buffered = true)This method will execute SQL and return a dynamic list.Example usage:var rows = connection.Query("select 1 A, 2 B union all select 3, 4"); ((int)rows[0].A).IsEqualTo(1);((int)rows[0].B).IsEqualTo(2);((int)rows[1].A).IsEqualTo(3);((int)rows[1].B).IsEqualTo(4); DbConnection con = this.GetConnection();return con.Query<t_So>("select * from dbo.t_so").ToList();//可以像上面一样，支持参数化查询，直接简单！
********************************************************************3、Execute a Command that returns no results
public static int Execute(this IDbConnection cnn, string sql, object param = null, SqlTransaction transaction = null)Example usage:connection.Execute(@" set nocount on create table #t(i int) set nocount off insert #t select @a a union all select @b set nocount on drop table #t", new {a=1, b=2 }) .IsEqualTo(2);
向数据据插入对象：
t_So so = new t_So();so.KeySeq = Guid.NewGuid();so.SoNo = this.sSoNo.Text;so.SoDate = GetValue.GetDateTime(this.sSoDate.Text);so.CustomerName = this.sCustomerName.Text;so.Remark = this.sRemark.Text; string strSQL = @"INSERT INTO dbo.t_so(KeySeq,SoNo,SoDate,CustomerName,Remark)VALUES(@KeySeq,@SoNo,@SoDate,@CustomerName,@Remark)";DbConnection con = this.GetConnection();//con.Execute(strSQL, new {KeySeq = so.KeySeq, SoNo = so.SoNo, SoDate = so.SoDate, CustomerName = so.CustomerName, Remark = so.Remark});con.Execute(strSQL, so);
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4、Execute a Command multiple times The same signature also allows you to conveniently and efficiently execute a command multiple times (for example to bulk-load data) Example usage:
connection.Execute(@"insert MyTable(colA, colB) values (@a, @b)", new[] { new { a=1, b=1 }, new { a=2, b=2 }, new { a=3, b=3 } } ).IsEqualTo(3); // 3 rows inserted: "1,1", "2,2" and "3,3"
This works for any parameter that implements IEnumerable for some T. 这个可以批量插入的，不错!
关于Dapper的使用笔记1
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