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

因为之前没有人提到它,所以还有Scaffold-DbContext

在NuGet Package Manager控制台类型如下: Microsoft.EntityFrameworkCore.SqlServer -OutputDir "输出目录"

其他回答

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

因为之前没有人提到它,所以还有Scaffold-DbContext

在NuGet Package Manager控制台类型如下: Microsoft.EntityFrameworkCore.SqlServer -OutputDir "输出目录"

Visual Studio杂志发表了这篇文章:

为SQL查询结果生成。net POCO类

它有一个可下载的项目,你可以构建,给它你的SQL信息,它会为你制作出类。

现在,如果该工具刚刚为SELECT、INSERT和UPDATE创建了SQL命令....

我喜欢用私有本地成员和公共访问器/突变器来设置我的类。 因此,我修改了上面的Alex脚本,以便为任何感兴趣的人做到这一点。

declare @TableName sysname = 'TABLE_NAME'
declare @result varchar(max) = 'public class ' + @TableName + '
{'

SET @result = @result + 
'
    public ' + @TableName + '()
    {}
';

select @result = @result + '
    private ' + ColumnType + ' ' + ' m_' + stuff(replace(ColumnName, '_', ''), 1, 1, lower(left(ColumnName, 1))) + ';'
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 ColumnType
    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
order by column_id

SET @result = @result + '
'

select @result = @result + '
    public ' + ColumnType + ' ' + ColumnName + ' { get { return m_' + stuff(replace(ColumnName, '_', ''), 1, 1, lower(left(ColumnName, 1))) + ';} set {m_' + stuff(replace(ColumnName, '_', ''), 1, 1, lower(left(ColumnName, 1))) + ' = value;} }' 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 ColumnType
    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
order by column_id

set @result = @result  + '
}'

print @result

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