描述

Dapper还使用了Async（异步）方法扩展了IDbConnection接口：

• ExecuteAsync
• QueryAsync
• QueryFirstAsync
• QueryFirstOrDefaultAsync
• QuerySingleAsync
• QuerySingleOrDefaultAsync
• QueryMultipleAsync

我们只在本教程中添加了非异步版本，以便于阅读。

ExecuteAsync

var sql = "Invoice_Insert";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var affectedRows = connection.ExecuteAsync(sql,
            new {Kind = InvoiceKind.WebInvoice, Code = "Single_Insert_1"},
            commandType: CommandType.StoredProcedure)
        .Result;
}

QueryAsync

var sql = "Invoice_Insert";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var invoices = connection.QueryAsync<Invoice>(sql).Result.ToList();
}

QueryFirstAsync

var sql = "SELECT * FROM Invoice WHERE InvoiceID = @InvoiceID;";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var invoice = connection.QueryFirstAsync<Invoice>(sql, new {InvoiceID = 1}).Result;
}

QueryFirstOrDefaultAsync

var sql = "SELECT * FROM Invoice WHERE InvoiceID = @InvoiceID;";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var invoice = connection.QueryFirstOrDefaultAsync<Invoice>(sql, new {InvoiceID = 1}).Result;
}

QuerySingleAsync

var sql = "SELECT * FROM Invoice WHERE InvoiceID = @InvoiceID;";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var invoice = connection.QuerySingleAsync<Invoice>(sql, new {InvoiceID = 1}).Result;
}

QuerySingleOrDefaultAsync

var sql = "SELECT * FROM Invoice WHERE InvoiceID = @InvoiceID;";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    var invoice = connection.QuerySingleOrDefaultAsync<Invoice>(sql, new {InvoiceID = 1}).Result;
}

QueryMultipleAsync

var sql = "SELECT * FROM Invoice; SELECT * FROM InvoiceItem;";

using (var connection = My.ConnectionFactory())
{
    connection.Open();

    using (var multi = connection.QueryMultipleAsync(sql, new { InvoiceID = 1 }).Result)
    {
        var invoice = multi.Read<Invoice>().First();
        var invoiceItems = multi.Read<InvoiceItem>().ToList();
    }
}