TopAttribute Class

.NET Standard 2.x | Current Version (1.0.1)

0.5.0-alpha

1.0.1 (current)

Denotes that a model class should limit the rows returned.

Namespace: SnapObjects.Data

Assembly: SnapObjects.Data.dll

Inheritance Constructor

System.Attribute

Syntax

   [AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct)]
   public class TopAttribute : Attribute

Constructors

Name	Description
TopAttribute(int number)	Initializes a new instance of the TopAttribute class.

Properties

Name	Return Type	Description
TopRows	int	Gets the maximum number of rows to be returned.

Remarks

The Top attribute denotes that a model class should add a TOP clause to the SQL SELECT statement to limit the rows returned.

Examples

The following code example demonstrates how to use the Top attribute. It applies the Top attribute to the DepartmentTop class, to add a TOP clause to the SQL SELECT statement to limit the rows returned.

Model: DepartmentTop

using SnapObjects.Data;
using System;
using System.ComponentModel.DataAnnotations;

namespace Appeon.ApiDoc.Models.School
{
    /// <summary>
    /// This model class maps to the dbo.Department table.
    /// </summary>
    [FromTable("Department", Schema = "dbo")]
    [Top(2)]

    public class DepartmentTop
    {
        [Key]
        public Int32 DepartmentID { get; set; }

        public String Name { get; set; }

        public Decimal Budget { get; set; }

        public DateTime StartDate { get; set; }

        public Int32? Administrator { get; set; }

    }
}

Example Method:

using SnapObjects.Data;
using Appeon.ApiDoc.Models.School;
using System;

namespace Appeon.ApiDoc.TopAttributeExamples
{
    public class TopAttributeExample
    {
        private SchoolContext _context;

        public TopAttributeExample(SchoolContext dataContext)
        {
            // Sets the data context.
            _context = dataContext;
        }

        public void Example()
        {
            // Gets the SQL statement.
            string sql = ModelSqlBuilder.GetBuilder<DepartmentTop>(_context).QuerySql;

            Console.WriteLine("SQL statement:");
            Console.WriteLine(sql);

            // Executes the SQL statement.
            var department = _context.SqlExecutor.Select<DepartmentTop>(sql);

            /* This code example produces the following output:
            
            SQL statement:
            SELECT
             TOP(2) [DepartmentID],
            [Name],
            [Budget],
            [StartDate],
            [Administrator]
            FROM [dbo].[Department]
            */
        }
    }
}

Applies to

.NET Standard

2.x