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
其他回答
你刚刚做了，只要你的表包含两列，并被称为'tblPeople'之类的东西。
您总是可以编写自己的SQL包装器。实际上我更喜欢这样做，我讨厌生成代码，以任何方式。
也许创建一个DAL类，并有一个名为GetPerson(int id)的方法，用于查询数据库中的person，然后从结果集中创建person对象。
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
设置@TableName为你的表名。
declare @TableName sysname = 'TableName'
declare @Result varchar(max) = 'public class ' + @TableName + '
{'
select @Result = @Result + '
public ' + ColumnType + NullableSign + ' ' + 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 'double'
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 'float'
when 'smalldatetime' then 'DateTime'
when 'smallint' then 'short'
when 'smallmoney' then 'decimal'
when 'text' then 'string'
when 'time' then 'TimeSpan'
when 'timestamp' then 'long'
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
order by ColumnId
set @Result = @Result + '
}'
print @Result
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
这篇文章救了我好几次。我只是想补充我的意见。 对于那些不喜欢使用orm，而是编写自己的DAL类的人来说，当你在一个表中有20个列，40个不同的表有各自的CRUD操作时，这是痛苦和浪费时间的。我重复了上面的代码，用于基于表实体和属性生成CRUD方法。
declare @TableName sysname = 'Tablename'
declare @Result varchar(max) = 'public class ' + @TableName + '
{'
select @Result = @Result + '
public ' + ColumnType + NullableSign + ' ' + 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 '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,
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
order by ColumnId
set @Result = @Result + '
}'
print @Result
declare @InitDataAccess varchar(max) = 'public class '+ @TableName +'DataAccess
{ '
declare @ListStatement varchar(max) ='public List<'+@TableName+'> Get'+@TableName+'List()
{
String conn = ConfigurationManager.ConnectionStrings["ConnectionNameInWeb.config"].ConnectionString;
var itemList = new List<'+@TableName+'>();
try
{
using (var sqlCon = new SqlConnection(conn))
{
sqlCon.Open();
var cmd = new SqlCommand
{
Connection = sqlCon,
CommandType = CommandType.StoredProcedure,
CommandText = "StoredProcedureSelectAll"
};
SqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
var item = new '+@TableName+'();
'
select @ListStatement = @ListStatement + '
item.'+ ColumnName + '= ('+ ColumnType + NullableSign +')reader["'+ColumnName+'"];
'
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 '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,
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
order by ColumnId
select @ListStatement = @ListStatement +'
itemList.Add(item);
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
return itemList;
}'
declare @GetIndividual varchar(max) =
'public '+@TableName+' Get'+@TableName+'()
{
String conn = ConfigurationManager.ConnectionStrings["ConnectionNameInWeb.config"].ConnectionString;
var item = new '+@TableName+'();
try
{
using (var sqlCon = new SqlConnection(conn))
{
sqlCon.Open();
var cmd = new SqlCommand
{
Connection = sqlCon,
CommandType = CommandType.StoredProcedure,
CommandText = "StoredProcedureSelectIndividual"
};
cmd.Parameters.AddWithValue("@ItemCriteria", item.id);
SqlDataReader reader = cmd.ExecuteReader();
if (reader.Read())
{'
select @GetIndividual = @GetIndividual + '
item.'+ ColumnName + '= ('+ ColumnType + NullableSign +')reader["'+ColumnName+'"];
'
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 '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,
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
order by ColumnId
select @GetIndividual = @GetIndividual +'
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
return item;
}'
declare @InsertStatement varchar(max) = 'public void Insert'+@TableName+'('+@TableName+' item)
{
String conn = ConfigurationManager.ConnectionStrings["ConnectionNameInWeb.config"].ConnectionString;
try
{
using (var sqlCon = new SqlConnection(conn))
{
sqlCon.Open();
var cmd = new SqlCommand
{
Connection = sqlCon,
CommandType = CommandType.StoredProcedure,
CommandText = "StoredProcedureInsert"
};
'
select @InsertStatement = @InsertStatement + '
cmd.Parameters.AddWithValue("@'+ColumnName+'", item.'+ColumnName+');
'
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 '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,
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
order by ColumnId
select @InsertStatement = @InsertStatement +'
cmd.ExecuteNonQuery();
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}'
declare @UpdateStatement varchar(max) = 'public void Update'+@TableName+'('+@TableName+' item)
{
String conn = ConfigurationManager.ConnectionStrings["ConnectionNameInWeb.config"].ConnectionString;
try
{
using (var sqlCon = new SqlConnection(conn))
{
sqlCon.Open();
var cmd = new SqlCommand
{
Connection = sqlCon,
CommandType = CommandType.StoredProcedure,
CommandText = "StoredProcedureUpdate"
};
cmd.Parameters.AddWithValue("@UpdateCriteria", item.Id);
'
select @UpdateStatement = @UpdateStatement + '
cmd.Parameters.AddWithValue("@'+ColumnName+'", item.'+ColumnName+');
'
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 '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,
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
order by ColumnId
select @UpdateStatement = @UpdateStatement +'
cmd.ExecuteNonQuery();
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}'
declare @EndDataAccess varchar(max) = '
}'
print @InitDataAccess
print @GetIndividual
print @InsertStatement
print @UpdateStatement
print @ListStatement
print @EndDataAccess
当然它不是防弹代码，并且可以改进。只是想为这个优秀的解决方案做点贡献
