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

要打印带有注释(摘要)的NULLABLE属性,使用这个。 这是对第一个答案的轻微修改

declare @TableName sysname = 'TableName'
declare @result varchar(max) = 'public class ' + @TableName + '
{'
select @result = @result 
+ CASE WHEN ColumnDesc IS NOT NULL THEN '
    /// <summary>
    /// ' + ColumnDesc + '
    /// </summary>' ELSE '' END
+ '
    public ' + ColumnType + ' ' + ColumnName + ' { get; set; }'
from
(
    select 
        replace(col.name, ' ', '_') ColumnName,
        column_id,
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            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 'int'
            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'
            else 'UNKNOWN_' + typ.name
        END + CASE WHEN col.is_nullable=1 AND typ.name NOT IN ('binary', 'varbinary', 'image', 'text', 'ntext', 'varchar', 'nvarchar', 'char', 'nchar') THEN '?' ELSE '' END ColumnType,
        colDesc.colDesc AS ColumnDesc
    from sys.columns col
        join sys.types typ on
            col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id
    OUTER APPLY (
    SELECT TOP 1 CAST(value AS NVARCHAR(max)) AS colDesc
    FROM
       sys.extended_properties
    WHERE
       major_id = col.object_id
       AND
       minor_id = COLUMNPROPERTY(major_id, col.name, 'ColumnId')
    ) colDesc            
    where object_id = object_id(@TableName)
) t
order by column_id

set @result = @result  + '
}'

print @result

其他回答

Java类生成

declare @TableName varchar(max) = 'Restaurants'
declare @Templete varchar(max) = ' 
     public @ColumnType @ColumnName ; // @ColumnDesc  
     public @ColumnType get@ColumnName()
     {
        return this.@ColumnName;
     }
     public void set@ColumnName(@ColumnType @ColumnName)
     {
        this.@ColumnName=@ColumnName;
     }

     '
declare @before varchar(max)='public class  @TableName  
{'
   
declare @after varchar(max)='
}'



declare @result varchar(max)

set @before =replace(@before,'@TableName',@TableName)

set @result=@before

select @result = @result 
+ replace(replace(replace(replace(replace(@Templete,'@ColumnType',ColumnType) ,'@ColumnName',ColumnName) ,'@ColumnDesc',ColumnDesc),'@ISPK',ISPK),'@max_length',max_length)

from  
(
    select 
    column_id,
    replace(col.name, ' ', '_') ColumnName,
    typ.name as sqltype,
    typ.max_length,
    is_identity,
    pkk.ISPK, 
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            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 'int'
            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'
            else 'UNKNOWN_' + typ.name
        END + CASE WHEN col.is_nullable=1 AND typ.name NOT IN ('binary', 'varbinary', 'image', 'text', 'ntext', 'varchar', 'nvarchar', 'char', 'nchar') THEN '?' ELSE '' END ColumnType,
      isnull(colDesc.colDesc,'') AS ColumnDesc 
    from sys.columns col
        join sys.types typ on
            col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id
            left join
            (
                SELECT c.name  AS 'ColumnName', CASE WHEN dd.pk IS NULL THEN 'false' ELSE 'true' END ISPK           
                FROM        sys.columns c
                    JOIN    sys.tables  t   ON c.object_id = t.object_id    
                    LEFT JOIN (SELECT   K.COLUMN_NAME , C.CONSTRAINT_TYPE as pk  
                        FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS K 
                            LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS C
                        ON K.TABLE_NAME = C.TABLE_NAME
                            AND K.CONSTRAINT_NAME = C.CONSTRAINT_NAME
                            AND K.CONSTRAINT_CATALOG = C.CONSTRAINT_CATALOG
                            AND K.CONSTRAINT_SCHEMA = C.CONSTRAINT_SCHEMA            
                        WHERE K.TABLE_NAME = @TableName) as dd
                     ON dd.COLUMN_NAME = c.name
                 WHERE       t.name = @TableName       
            ) pkk  on ColumnName=col.name

    OUTER APPLY (
    SELECT TOP 1 CAST(value AS NVARCHAR(max)) AS colDesc
    FROM
       sys.extended_properties
    WHERE
       major_id = col.object_id
       AND
       minor_id = COLUMNPROPERTY(major_id, col.name, 'ColumnId')
    ) colDesc      
    where object_id = object_id(@TableName)

    ) t

    set @result=@result+@after

    select @result
    --print @result

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

我无法让亚历克斯的答案在Sql Server 2008 R2上工作。所以,我用同样的基本原理重写了它。它现在支持模式,并且对列属性映射(包括将可为空的日期类型映射为可为空的c#值类型)进行了一些修复。下面是Sql语句:

   DECLARE @TableName VARCHAR(MAX) = 'NewsItem' -- Replace 'NewsItem' with your table name
    DECLARE @TableSchema VARCHAR(MAX) = 'Markets' -- Replace 'Markets' with your schema name
    DECLARE @result varchar(max) = ''

    SET @result = @result + 'using System;' + CHAR(13) + CHAR(13) 

    IF (@TableSchema IS NOT NULL) 
    BEGIN
        SET @result = @result + 'namespace ' + @TableSchema  + CHAR(13) + '{' + CHAR(13) 
    END

    SET @result = @result + 'public class ' + @TableName + CHAR(13) + '{' + CHAR(13) 

    SET @result = @result + '#region Instance Properties' + CHAR(13)  

   SELECT
      @result = @result + CHAR(13)
      + ' public ' + ColumnType + ' ' + ColumnName + ' { get; set; } ' + CHAR(13)
    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 'bool?'
            ELSE 'bool'
          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 'int?'
            ELSE 'int'
          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 'Byte[]'
        WHEN 'tinyint' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Byte?'
            ELSE 'Byte'
          END
        WHEN 'uniqueidentifier' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Guid?'
            ELSE 'Guid'
          END
        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(@TableSchema, c.TABLE_SCHEMA) = c.TABLE_SCHEMA) t
    ORDER BY t.ORDINAL_POSITION

    SET @result = @result + CHAR(13) + '#endregion Instance Properties' + CHAR(13)  

    SET @result = @result  + '}' + CHAR(13)

    IF (@TableSchema IS NOT NULL) 
    BEGIN
        SET @result = @result + CHAR(13) + '}' 
    END

    PRINT @result

它生成的c#代码如下所示:

using System;

namespace Markets
{
    public class NewsItem        {
        #region Instance Properties

        public Int32 NewsItemID { get; set; }

        public Int32? TextID { get; set; }

        public String Description { get; set; }

        #endregion Instance Properties
    }

}

It may be an idea to use EF, Linq to Sql, or even Scaffolding; however, there are times when a piece of coding like this comes in handy. Frankly, I do not like using EF navigation properties where the code it generates made 19,200 separate database calls to populate a 1000 row grid. This could have been achieved in a single database call. Nonetheless, it could just be that your technical architect does not want you to use EF and the like. So, you have to revert to code like this... Incidentally, it may also be an idea to decorate each of the properties with attributes for DataAnnotations, etc., but I'm keeping this strictly POCO.

编辑 修正了时间戳和Guid?

我很困惑你想要从这里得到什么,但这里是在设计你想要设计的东西时的一般选择。

在Visual Studio版本中使用内置的ORM。 自己编写一个,类似于您的代码示例。通常情况下,如果你不确定怎么做,教程是你最好的朋友。 使用另一种ORM,如NHibernate。

从顶部回复略有修改:

declare @TableName sysname = 'HistoricCommand'

declare @Result varchar(max) = '[System.Data.Linq.Mapping.Table(Name = "' + @TableName + '")]
public class Dbo' + @TableName + '
{'

select @Result = @Result + '
    [System.Data.Linq.Mapping.Column(Name = "' + t.ColumnName + '", IsPrimaryKey = ' + pkk.ISPK + ')]
    public ' + ColumnType + NullableSign + ' ' + t.ColumnName + ' { get; set; }
'
from
(
    select 
        replace(col.name, ' ', '_') ColumnName,
        column_id ColumnId,
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            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 'int'
            when 'money' then 'decimal'
            when 'nchar' then 'string'
            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'
            else 'UNKNOWN_' + typ.name
        end ColumnType,
        case 
            when col.is_nullable = 1 and typ.name in ('bigint', 'bit', 'date', 'datetime', 'datetime2', 'datetimeoffset', 'decimal', 'float', 'int', 'money', 'numeric', 'real', 'smalldatetime', 'smallint', 'smallmoney', 'time', 'tinyint', 'uniqueidentifier') 
            then '?' 
            else '' 
        end NullableSign
    from sys.columns col
        join sys.types typ on
            col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id         
    where object_id = object_id(@TableName) 
) t, 
(
                SELECT c.name  AS 'ColumnName', CASE WHEN dd.pk IS NULL THEN 'false' ELSE 'true' END ISPK           
                FROM        sys.columns c
                    JOIN    sys.tables  t   ON c.object_id = t.object_id    
                    LEFT JOIN (SELECT   K.COLUMN_NAME , C.CONSTRAINT_TYPE as pk  
                        FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS K 
                            LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS C
                        ON K.TABLE_NAME = C.TABLE_NAME
                            AND K.CONSTRAINT_NAME = C.CONSTRAINT_NAME
                            AND K.CONSTRAINT_CATALOG = C.CONSTRAINT_CATALOG
                            AND K.CONSTRAINT_SCHEMA = C.CONSTRAINT_SCHEMA            
                        WHERE K.TABLE_NAME = @TableName) as dd
                     ON dd.COLUMN_NAME = c.name
                 WHERE       t.name = @TableName            
            ) pkk
where pkk.ColumnName = t.ColumnName
order by ColumnId

set @Result = @Result  + '
}'

print @Result

这使得输出需要完整的LINQ在c#声明

[System.Data.Linq.Mapping.Table(Name = "HistoricCommand")]
public class DboHistoricCommand
{
    [System.Data.Linq.Mapping.Column(Name = "HistoricCommandId", IsPrimaryKey = true)]
    public int HistoricCommandId { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "PHCloudSoftwareInstanceId", IsPrimaryKey = true)]
    public int PHCloudSoftwareInstanceId { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "CommandType", IsPrimaryKey = false)]
    public int CommandType { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "InitiatedDateTime", IsPrimaryKey = false)]
    public DateTime InitiatedDateTime { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "CompletedDateTime", IsPrimaryKey = false)]
    public DateTime CompletedDateTime { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "WasSuccessful", IsPrimaryKey = false)]
    public bool WasSuccessful { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "Message", IsPrimaryKey = false)]
    public string Message { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "ResponseData", IsPrimaryKey = false)]
    public string ResponseData { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "Message_orig", IsPrimaryKey = false)]
    public string Message_orig { get; set; }

    [System.Data.Linq.Mapping.Column(Name = "Message_XX", IsPrimaryKey = false)]
    public string Message_XX { get; set; }

}