如何从SQL Server表对象生成类?

我说的不是使用ORM。我只需要创建实体(简单类)。喜欢的东西:

    public class Person 
    {
        public string Name { get;set; }
        public string Phone { get;set; }
    }

给定一个表,比如:

+----+-------+----------------+
| ID | Name  |     Phone      |
+----+-------+----------------+
|  1 | Alice | (555) 555-5550 |
|  2 | Bob   | (555) 555-5551 |
|  3 | Cathy | (555) 555-5552 |
+----+-------+----------------+



当前回答

我尝试使用上面的建议,并在这个过程中改进了这个线程中的解决方案。

让我们假设您使用实现PropertyChanged事件的基类(在本例中为ObservableObject),您将像这样做。有一天我可能会在我的博客上写一篇博客文章 sqljana.wordpress.com

请将前三个变量的值替换为:

    --These three things have to be substituted (when called from Powershell, they are replaced before execution)
DECLARE @Schema VARCHAR(MAX) = N'&Schema'
DECLARE @TableName VARCHAR(MAX) = N'&TableName'
DECLARE @Namespace VARCHAR(MAX) = N'&Namespace'

DECLARE @CRLF VARCHAR(2) = CHAR(13) + CHAR(10);
DECLARE @result VARCHAR(max) = ' '

DECLARE @PrivateProp VARCHAR(100) = @CRLF + 
                CHAR(9) + CHAR(9) + 'private <ColumnType> _<ColumnName>;';
DECLARE @PublicProp VARCHAR(255) = @CRLF + 
                CHAR(9) + CHAR(9) + 'public <ColumnType> <ColumnName> '  + @CRLF +
                CHAR(9) + CHAR(9) + '{ ' + @CRLF +
                CHAR(9) + CHAR(9) + '   get { return _<ColumnName>; } ' + @CRLF +
                CHAR(9) + CHAR(9) + '   set ' + @CRLF +
                CHAR(9) + CHAR(9) + '   { ' + @CRLF +
                CHAR(9) + CHAR(9) + '       _<ColumnName> = value;' + @CRLF +
                CHAR(9) + CHAR(9) + '       base.RaisePropertyChanged();' + @CRLF +
                CHAR(9) + CHAR(9) + '   } ' + @CRLF +
                CHAR(9) + CHAR(9) + '}' + @CRLF;

DECLARE @RPCProc VARCHAR(MAX) = @CRLF +         
                CHAR(9) + CHAR(9) + 'public event PropertyChangedEventHandler PropertyChanged; ' + @CRLF +
                CHAR(9) + CHAR(9) + 'private void RaisePropertyChanged( ' + @CRLF +
                CHAR(9) + CHAR(9) + '       [CallerMemberName] string caller = "" ) ' + @CRLF +
                CHAR(9) + CHAR(9) + '{  ' + @CRLF +
                CHAR(9) + CHAR(9) + '   if (PropertyChanged != null)  ' + @CRLF +
                CHAR(9) + CHAR(9) + '   { ' + @CRLF +
                CHAR(9) + CHAR(9) + '       PropertyChanged( this, new PropertyChangedEventArgs( caller ) );  ' + @CRLF +
                CHAR(9) + CHAR(9) + '   } ' + @CRLF +
                CHAR(9) + CHAR(9) + '}';

DECLARE @PropChanged VARCHAR(200) =  @CRLF +            
                CHAR(9) + CHAR(9) + 'protected override void AfterPropertyChanged(string propertyName) ' + @CRLF +
                CHAR(9) + CHAR(9) + '{ ' + @CRLF +
                CHAR(9) + CHAR(9) + '   System.Diagnostics.Debug.WriteLine("' + @TableName + ' property changed: " + propertyName); ' + @CRLF +
                CHAR(9) + CHAR(9) + '}';

SET @result = 'using System;' + @CRLF + @CRLF +
                'using MyCompany.Business;' + @CRLF + @CRLF +
                'namespace ' + @Namespace  + @CRLF + '{' + @CRLF +
                '   public class ' + @TableName + ' : ObservableObject' + @CRLF + 
                '   {' + @CRLF +
                '   #region Instance Properties' + @CRLF 

SELECT @result = @result
                 + 
                REPLACE(
                            REPLACE(@PrivateProp
                            , '<ColumnName>', ColumnName)
                        , '<ColumnType>', ColumnType)
                +                           
                REPLACE(
                            REPLACE(@PublicProp
                            , '<ColumnName>', ColumnName)
                        , '<ColumnType>', ColumnType)                   
FROM
(
    SELECT  c.COLUMN_NAME   AS ColumnName 
        , CASE c.DATA_TYPE   
            WHEN 'bigint' THEN
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Int64?' ELSE 'Int64' END
            WHEN 'binary' THEN 'Byte[]'
            WHEN 'bit' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Boolean?' ELSE 'Boolean' END            
            WHEN 'char' THEN 'String'
            WHEN 'date' THEN
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTime?' ELSE 'DateTime' END                        
            WHEN 'datetime' THEN
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTime?' ELSE 'DateTime' END                        
            WHEN 'datetime2' THEN  
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTime?' ELSE 'DateTime' END                        
            WHEN 'datetimeoffset' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTimeOffset?' ELSE 'DateTimeOffset' END                                    
            WHEN 'decimal' THEN  
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Decimal?' ELSE 'Decimal' END                                    
            WHEN 'float' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Single?' ELSE 'Single' END                                    
            WHEN 'image' THEN 'Byte[]'
            WHEN 'int' THEN  
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Int32?' ELSE 'Int32' END
            WHEN 'money' THEN
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Decimal?' ELSE 'Decimal' END                                                
            WHEN 'nchar' THEN 'String'
            WHEN 'ntext' THEN 'String'
            WHEN 'numeric' THEN
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Decimal?' ELSE 'Decimal' END                                                            
            WHEN 'nvarchar' THEN 'String'
            WHEN 'real' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Double?' ELSE 'Double' END                                                                        
            WHEN 'smalldatetime' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTime?' ELSE 'DateTime' END                                    
            WHEN 'smallint' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Int16?' ELSE 'Int16'END            
            WHEN 'smallmoney' THEN  
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Decimal?' ELSE 'Decimal' END                                                                        
            WHEN 'text' THEN 'String'
            WHEN 'time' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'TimeSpan?' ELSE 'TimeSpan' END                                                                                    
            WHEN 'timestamp' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'DateTime?' ELSE 'DateTime' END                                    
            WHEN 'tinyint' THEN 
                CASE C.IS_NULLABLE
                    WHEN 'YES' THEN 'Byte?' ELSE 'Byte' END                                                
            WHEN 'uniqueidentifier' THEN 'Guid'
            WHEN 'varbinary' THEN 'Byte[]'
            WHEN 'varchar' THEN 'String'
            ELSE 'Object'
        END AS ColumnType
        , c.ORDINAL_POSITION 
FROM    INFORMATION_SCHEMA.COLUMNS c
WHERE   c.TABLE_NAME = @TableName 
    AND ISNULL(@Schema, c.TABLE_SCHEMA) = c.TABLE_SCHEMA  
) t
ORDER BY t.ORDINAL_POSITION

SELECT @result = @result + @CRLF + 
                CHAR(9) + '#endregion Instance Properties' + @CRLF +
                --CHAR(9) + @RPCProc + @CRLF +
                CHAR(9) + @PropChanged + @CRLF +
                CHAR(9) + '}' + @CRLF +
                @CRLF + '}' 
--SELECT @result
PRINT @result

基类基于Josh Smith的文章 从http://joshsmithonwpf.wordpress.com/2007/08/29/a-base-class-which-implements-inotifypropertychanged/

我确实将类重命名为ObservableObject,并使用CallerMemberName属性利用了c# 5的一个特性

//From http://joshsmithonwpf.wordpress.com/2007/08/29/a-base-class-which-implements-inotifypropertychanged/
//
//Jana's change: Used c# 5 feature to bypass passing in the property name using [CallerMemberName] 
//  protected void RaisePropertyChanged([CallerMemberName] string propertyName = "")

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.CompilerServices;

namespace MyCompany.Business
{

    /// <summary>
    /// Implements the INotifyPropertyChanged interface and 
    /// exposes a RaisePropertyChanged method for derived 
    /// classes to raise the PropertyChange event.  The event 
    /// arguments created by this class are cached to prevent 
    /// managed heap fragmentation.
    /// </summary>
    [Serializable]
    public abstract class ObservableObject : INotifyPropertyChanged
    {
        #region Data

        private static readonly Dictionary<string, PropertyChangedEventArgs> eventArgCache;
        private const string ERROR_MSG = "{0} is not a public property of {1}";

        #endregion // Data

        #region Constructors

        static ObservableObject()
        {
            eventArgCache = new Dictionary<string, PropertyChangedEventArgs>();
        }

        protected ObservableObject()
        {
        }

        #endregion // Constructors

        #region Public Members

        /// <summary>
        /// Raised when a public property of this object is set.
        /// </summary>
        [field: NonSerialized]
        public event PropertyChangedEventHandler PropertyChanged;

        /// <summary>
        /// Returns an instance of PropertyChangedEventArgs for 
        /// the specified property name.
        /// </summary>
        /// <param name="propertyName">
        /// The name of the property to create event args for.
        /// </param>        
        public static PropertyChangedEventArgs
            GetPropertyChangedEventArgs(string propertyName)
        {
            if (String.IsNullOrEmpty(propertyName))
                throw new ArgumentException(
                    "propertyName cannot be null or empty.");

            PropertyChangedEventArgs args;

            // Get the event args from the cache, creating them
            // and adding to the cache if necessary.
            lock (typeof(ObservableObject))
            {
                bool isCached = eventArgCache.ContainsKey(propertyName);
                if (!isCached)
                {
                    eventArgCache.Add(
                        propertyName,
                        new PropertyChangedEventArgs(propertyName));
                }

                args = eventArgCache[propertyName];
            }

            return args;
        }

        #endregion // Public Members

        #region Protected Members

        /// <summary>
        /// Derived classes can override this method to
        /// execute logic after a property is set. The 
        /// base implementation does nothing.
        /// </summary>
        /// <param name="propertyName">
        /// The property which was changed.
        /// </param>
        protected virtual void AfterPropertyChanged(string propertyName)
        {
        }

        /// <summary>
        /// Attempts to raise the PropertyChanged event, and 
        /// invokes the virtual AfterPropertyChanged method, 
        /// regardless of whether the event was raised or not.
        /// </summary>
        /// <param name="propertyName">
        /// The property which was changed.
        /// </param>
        protected void RaisePropertyChanged([CallerMemberName] string propertyName = "")
        {
            this.VerifyProperty(propertyName);

            PropertyChangedEventHandler handler = this.PropertyChanged;
            if (handler != null)
            {
                // Get the cached event args.
                PropertyChangedEventArgs args =
                    GetPropertyChangedEventArgs(propertyName);

                // Raise the PropertyChanged event.
                handler(this, args);
            }

            this.AfterPropertyChanged(propertyName);
        }

        #endregion // Protected Members

        #region Private Helpers

        [Conditional("DEBUG")]
        private void VerifyProperty(string propertyName)
        {
            Type type = this.GetType();

            // Look for a public property with the specified name.
            PropertyInfo propInfo = type.GetProperty(propertyName);

            if (propInfo == null)
            {
                // The property could not be found,
                // so alert the developer of the problem.

                string msg = string.Format(
                    ERROR_MSG,
                    propertyName,
                    type.FullName);

                Debug.Fail(msg);
            }
        }

        #endregion // Private Helpers
    }
}

下面是你们会更喜欢的部分。我构建了一个Powershell脚本来为SQL数据库中的所有表生成。它是基于一个名为Chad Miller的Powershell大师的Invoke-SQLCmd2 cmdlet,可以从这里下载: http://gallery.technet.microsoft.com/ScriptCenter/7985b7ef-ed89-4dfd-b02a-433cc4e30894/

一旦有了cmdlet,为所有表生成的Powershell脚本就变得简单了(一定要用特定的值替换变量)。

. C:\MyScripts\Invoke-Sqlcmd2.ps1

$serverInstance = "MySQLInstance"
$databaseName = "MyDb"
$generatorSQLFile = "C:\MyScripts\ModelGen.sql" 
$tableListSQL = "SELECT name FROM $databaseName.sys.tables"
$outputFolder = "C:\MyScripts\Output\"
$namespace = "MyCompany.Business"

$placeHolderSchema = "&Schema"
$placeHolderTableName = "&TableName"
$placeHolderNamespace = "&Namespace"

#Get the list of tables in the database to generate c# models for
$tables = Invoke-Sqlcmd2 -ServerInstance $serverInstance -Database $databaseName -Query $tableListSQL -As DataRow -Verbose

foreach ($table in $tables)
{
    $table1 = $table[0]
    $outputFile = "$outputFolder\$table1.cs"


    #Replace variables with values (returns an array that we convert to a string to use as query)
    $generatorSQLFileWSubstitutions = (Get-Content $generatorSQLFile).
                                            Replace($placeHolderSchema,"dbo").
                                            Replace($placeHolderTableName, $table1).
                                            Replace($placeHolderNamespace, $namespace) | Out-String

    "Ouputing for $table1 to $outputFile"

    #The command generates .cs file content for model using "PRINT" statements which then gets written to verbose output (stream 4)
    # ...capture the verbose output and redirect to a file
    (Invoke-Sqlcmd2 -ServerInstance $serverInstance -Database $databaseName -Query $generatorSQLFileWSubstitutions -Verbose) 4> $outputFile

}

其他回答

Oracle DB的另一个解决方案-> c#

单查询 无功能无步骤 Mulitple表

添加DataAnnotations

(例子) (需要) (表) (StringLength) (列) 可以为空

查询

https://gist.github.com/omansak/f19eefffd2d639ac72a1f4b506d8471a

输出

[Table("AGENTS")]
public class Agents
{
    [Key]
    [Required]
    [Column("INT_ID", TypeName = "NUMBER(10,0)", Order = 1)]
    public long IntId { get; set; }
    [Key]
    [Required]
    [StringLength(15)]
    [Column("REFERENCE_CODE", TypeName = "VARCHAR2(15)", Order = 2)]
    public string ReferenceCode { get; set; }
    [Required]
    [Column("PARENT_INT_ID", TypeName = "NUMBER(10,0)", Order = 3)]
    public long ParentIntId { get; set; }
    [Required]
    [StringLength(200)]
    [Column("TITLE", TypeName = "VARCHAR2(200)", Order = 4)]
    public string Title { get; set; }
    [Required]
    [Column("START_DATE", TypeName = "DATE", Order = 5)]
    public DateTime StartDate { get; set; }
    [Required]
    [Column("END_DATE", TypeName = "DATE", Order = 6)]
    public DateTime EndDate { get; set; }
    [Required]
    [StringLength(1)]
    [Column("AGENT_TYPE", TypeName = "VARCHAR2(1)", Order = 7)]
    public string AgentType { get; set; }
    [Required]
    [Column("CREATE_DATE", TypeName = "DATE", Order = 8)]
    public DateTime CreateDate { get; set; }
    [Required]
    [StringLength(32)]
    [Column("CREATE_USER", TypeName = "VARCHAR2(32)", Order = 9)]
    public string CreateUser { get; set; }
    [StringLength(200)]
    [Column("RESPONSIBLE_CONTACT", TypeName = "VARCHAR2(200)", Order = 10)]
    public string ResponsibleContact { get; set; }
    [StringLength(100)]
    [Column("RESPONSIBLE_TITLE", TypeName = "VARCHAR2(100)", Order = 11)]
    public string ResponsibleTitle { get; set; }
    [StringLength(100)]
    [Column("AGENCY_PLATE_NO", TypeName = "VARCHAR2(100)", Order = 12)]
    public string AgencyPlateNo { get; set; }
    [Column("AGENCY_COVER_AMOUNT", TypeName = "NUMBER(24,2)", Order = 13)]
    public double? AgencyCoverAmount { get; set; }
    [StringLength(100)]
    [Column("MERSIS_NO", TypeName = "VARCHAR2(100)", Order = 14)]
    public string MersisNo { get; set; }
    [StringLength(100)]
    [Column("TECH_PERSONEL_NO", TypeName = "VARCHAR2(100)", Order = 15)]
    public string TechPersonelNo { get; set; }
    [StringLength(100)]
    [Column("TECH_PERSONEL_NAME", TypeName = "VARCHAR2(100)", Order = 16)]
    public string TechPersonelName { get; set; }
    [Column("COVER_END_DATE", TypeName = "DATE", Order = 17)]
    public DateTime? CoverEndDate { get; set; }
    [Column("BRANCH_NUMBER", TypeName = "NUMBER(10,0)", Order = 18)]
    public long? BranchNumber { get; set; }
    [Column("ACTION_NUMBER", TypeName = "NUMBER(10,0)", Order = 19)]
    public long? ActionNumber { get; set; }
    [Column("CLUB_PARTICIPATION_COUNT", TypeName = "NUMBER(10,0)", Order = 20)]
    public long? ClubParticipationCount { get; set; }
    [Column("AGENCY_CONTRACT_DATE", TypeName = "DATE", Order = 21)]
    public DateTime? AgencyContractDate { get; set; }
    [StringLength(200)]
    [Column("KEP_ADDRESS", TypeName = "VARCHAR2(200)", Order = 22)]
    public string KepAddress { get; set; }
}

我将几个基于SQL的答案(主要是Alex Aza的根答案)打包到kassify中,这是一个控制台应用程序,可以一次性为指定的数据库生成所有类:


例如,给定一个Users表,它是这样的:

+----+------------------+-----------+---------------------+
| Id |       Name       | Username  |        Email        |
+----+------------------+-----------+---------------------+
|  1 | Leanne Graham    | Bret      | Sincere@april.biz   |
|  2 | Ervin Howell     | Antonette | Shanna@melissa.tv   |
|  3 | Clementine Bauch | Samantha  | Nathan@yesenia.net  |
+----+------------------+-----------+---------------------+

klassify将生成一个名为Users.cs的文件,看起来像这样:

    public class User 
    {
        public int Id {get; set; }
        public string Name { get;set; }
        public string Username { get; set; }
        public string Email { get; set; }
    }

它将为每个表输出一个文件。丢弃你不用的东西。

使用

 --out, -o:
        output directory     << defaults to the current directory >>
 --user, -u:
        sql server user id   << required >>
 --password, -p:
        sql server password  << required >>
 --server, -s:
        sql server           << defaults to localhost >>
 --database, -d:
        sql database         << required >>
 --timeout, -t:
        connection timeout   << defaults to 30 >>
 --help, -h:
        show help

我只是想表达我的意见

0) QueryFirst https://marketplace.visualstudio.com/items?itemName=bbsimonbb.QueryFirst Query-first is a visual studio extension for working intelligently with SQL in C# projects. Use the provided .sql template to develop your queries. When you save the file, Query-first runs your query, retrieves the schema and generates two classes and an interface: a wrapper class with methods Execute(), ExecuteScalar(), ExecuteNonQuery() etc, its corresponding interface, and a POCO encapsulating a line of results.

1) Sql2Objects 从查询结果开始创建类(但不是DAL)

2) https://learn.microsoft.com/en-us/ef/ef6/resources/tools

3) https://visualstudiomagazine.com/articles/2012/12/11/sqlqueryresults-code-generation.aspx

4) http://www.codesmithtools.com/product/generator#features

VB版

declare @TableName sysname = 'myTableName'
declare @prop varchar(max)
PRINT 'Public Class ' + @TableName
declare props cursor for
select distinct ' public property ' + ColumnName + ' AS ' + ColumnType AS prop
from ( 
    select  
        replace(col.name, ' ', '_') ColumnName,  column_id, 
        case typ.name  
            when 'bigint' then 'long' 
            when 'binary' then 'byte[]' 
            when 'bit' then 'boolean' 
            when 'char' then 'string' 
            when 'date' then 'DateTime' 
            when 'datetime' then 'DateTime' 
            when 'datetime2' then 'DateTime' 
            when 'datetimeoffset' then 'DateTimeOffset' 
            when 'decimal' then 'decimal' 
            when 'float' then 'float' 
            when 'image' then 'byte[]' 
            when 'int' then 'integer' 
            when 'money' then 'decimal' 
            when 'nchar' then 'char' 
            when 'ntext' then 'string' 
            when 'numeric' then 'decimal' 
            when 'nvarchar' then 'string' 
            when 'real' then 'double' 
            when 'smalldatetime' then 'DateTime' 
            when 'smallint' then 'short' 
            when 'smallmoney' then 'decimal' 
            when 'text' then 'string' 
            when 'time' then 'TimeSpan' 
            when 'timestamp' then 'DateTime' 
            when 'tinyint' then 'byte' 
            when 'uniqueidentifier' then 'Guid' 
            when 'varbinary' then 'byte[]' 
            when 'varchar' then 'string' 
        end ColumnType 
    from sys.columns col join sys.types typ on col.system_type_id = typ.system_type_id 
    where object_id = object_id(@TableName) 
) t 
order by prop
open props
FETCH NEXT FROM props INTO @prop
WHILE @@FETCH_STATUS = 0
BEGIN
    print @prop
    FETCH NEXT FROM props INTO @prop
END
close props
DEALLOCATE props
PRINT 'End Class'

是的,这些是伟大的,如果你使用一个简单的ORM像Dapper。

如果你使用。net,你可以在运行时使用WriteXmlSchema方法用任何数据集生成XSD文件。http://msdn.microsoft.com/en-us/library/xt7k72x8 (v = vs.110) . aspx

是这样的:

using (SqlConnection cnn = new SqlConnection(mConnStr)) {
DataSet Data = new DataSet();
cnn.Open();
string sql = "SELECT * FROM Person";

using (SqlDataAdapter Da = new SqlDataAdapter(sql, cnn))
{
try
{
    Da.Fill(Data);
    Da.TableMappings.Add("Table", "Person");
    Data.WriteXmlSchema(@"C:\Person.xsd");
}
catch (Exception ex)
{ MessageBox.Show(ex.Message); }
}
cnn.Close();

从那里,您可以使用xsd.exe创建一个可从开发人员命令提示符序列化XML的类。 http://msdn.microsoft.com/en-us/library/x6c1kb0s (v = vs.110) . aspx

是这样的:

xsd C:\Person.xsd /classes /language:CS