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。

其他回答

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

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

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....

商业化,但codessmith Generator做到了:http://www.codesmithtools.com/product/generator

有点晚了,但我已经创建了一个web工具来帮助创建一个c#(或其他)对象从SQL结果,SQL表和SQL SP。

sql2object.com

这可以让你安全地输入所有的属性和类型。

如果无法识别类型,则将选择默认类型。