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

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

其他回答

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

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; }

}

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'

为了感谢Alex的解决方案和Guilherme的要求,我为MySQL生成c#类做了这个

set @schema := 'schema_name';
set @table := 'table_name';
SET group_concat_max_len = 2048;
SELECT 
    concat('public class ', @table, '\n{\n', GROUP_CONCAT(a.property_ SEPARATOR '\n'), '\n}') class_
FROM 
    (select
        CONCAT(
        '\tpublic ',
        case 
            when DATA_TYPE = 'bigint' then 'long'
            when DATA_TYPE = 'BINARY' then 'byte[]'
            when DATA_TYPE = 'bit' then 'bool'
            when DATA_TYPE = 'char' then 'string'
            when DATA_TYPE = 'date' then 'DateTime'
            when DATA_TYPE = 'datetime' then 'DateTime'
            when DATA_TYPE = 'datetime2' then 'DateTime'
            when DATA_TYPE = 'datetimeoffset' then 'DateTimeOffset'
            when DATA_TYPE = 'decimal' then 'decimal'
            when DATA_TYPE = 'double' then 'double'
            when DATA_TYPE = 'float' then 'float'
            when DATA_TYPE = 'image' then 'byte[]'
            when DATA_TYPE = 'int' then 'int'
            when DATA_TYPE = 'money' then 'decimal'
            when DATA_TYPE = 'nchar' then 'char'
            when DATA_TYPE = 'ntext' then 'string'
            when DATA_TYPE = 'numeric' then 'decimal'
            when DATA_TYPE = 'nvarchar' then 'string'
            when DATA_TYPE = 'real' then 'double'
            when DATA_TYPE = 'smalldatetime' then 'DateTime'
            when DATA_TYPE = 'smallint' then 'short'
            when DATA_TYPE = 'smallmoney' then 'decimal'
            when DATA_TYPE = 'text' then 'string'
            when DATA_TYPE = 'time' then 'TimeSpan'
            when DATA_TYPE = 'timestamp' then 'DateTime'
            when DATA_TYPE = 'tinyint' then 'byte'
            when DATA_TYPE = 'uniqueidentifier' then 'Guid'
            when DATA_TYPE = 'varbinary' then 'byte[]'
            when DATA_TYPE = 'varchar' then 'string'
            else '_UNKNOWN_'
        end, ' ', 
        COLUMN_NAME, ' {get; set;}') as property_
    FROM INFORMATION_SCHEMA.COLUMNS
    WHERE table_name = @table AND table_schema = @schema) a
;

谢谢Alex和Guilherme!

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