有人用C＃函数将列的SQL数据类型映射到它的CLR等价物吗？

I'm sitting down to write a massive switch() statement to turn SQL datatypes into CLR datatypes in order to generate classes from MSSQL stored procedures. I'm using this chart as a reference. Before I get too far into what will probably take all day and be a huge pain to fully test, I'd like to call out to the SO community to see if anyone else has already written or found something in C# to accomplish this seemingly common and assuredly tedious task.

我坐下来编写一个庞大的switch()语句,将SQL数据类型转换为CLR数据类型,以便从MSSQL存储过程生成类。我正在使用此图表作为参考。在我进入可能需要一整天并且完全测试的巨大痛苦之前,我想呼吁SO社区,看看是否有其他人已经在C#中编写或发现了一些看似常见的东西确定无聊的任务。

12 个解决方案

#1

This is the one we use. You may want to tweak it (e.g. nullable/non-nullable types etc.) but it should save you most of the typing.

这是我们使用的那个。您可能想要调整它(例如可空/不可空类型等)但它应该可以节省大部分输入。

public static Type GetClrType(SqlDbType sqlType)
{
    switch (sqlType)
    {
        case SqlDbType.BigInt:
            return typeof(long?);

        case SqlDbType.Binary:
        case SqlDbType.Image:
        case SqlDbType.Timestamp:
        case SqlDbType.VarBinary:
            return typeof(byte[]);

        case SqlDbType.Bit:
            return typeof(bool?);

        case SqlDbType.Char:
        case SqlDbType.NChar:
        case SqlDbType.NText:
        case SqlDbType.NVarChar:
        case SqlDbType.Text:
        case SqlDbType.VarChar:
        case SqlDbType.Xml:
            return typeof(string);

        case SqlDbType.DateTime:
        case SqlDbType.SmallDateTime:
        case SqlDbType.Date:
        case SqlDbType.Time:
        case SqlDbType.DateTime2:
            return typeof(DateTime?);

        case SqlDbType.Decimal:
        case SqlDbType.Money:
        case SqlDbType.SmallMoney:
            return typeof(decimal?);

        case SqlDbType.Float:
            return typeof(double?);

        case SqlDbType.Int:
            return typeof(int?);

        case SqlDbType.Real:
            return typeof(float?);

        case SqlDbType.UniqueIdentifier:
            return typeof(Guid?);

        case SqlDbType.SmallInt:
            return typeof(short?);

        case SqlDbType.TinyInt:
            return typeof(byte?);

        case SqlDbType.Variant:
        case SqlDbType.Udt:
            return typeof(object);

        case SqlDbType.Structured:
            return typeof(DataTable);

        case SqlDbType.DateTimeOffset:
            return typeof(DateTimeOffset?);

        default:
            throw new ArgumentOutOfRangeException("sqlType");
    }
}

#2

    /****** Object:  Table [dbo].[DbVsCSharpTypes]    Script Date: 03/20/2010 03:07:56 ******/
    IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[DbVsCSharpTypes]') 
    AND type in (N'U'))
    DROP TABLE [dbo].[DbVsCSharpTypes]
    GO

    /****** Object:  Table [dbo].[DbVsCSharpTypes]    Script Date: 03/20/2010 03:07:56 ******/
    SET ANSI_NULLS ON
    GO

    SET QUOTED_IDENTIFIER ON
    GO

    CREATE TABLE [dbo].[DbVsCSharpTypes](
        [DbVsCSharpTypesId] [int] IDENTITY(1,1) NOT NULL,
        [Sql2008DataType] [varchar](200) NULL,
        [CSharpDataType] [varchar](200) NULL,
        [CLRDataType] [varchar](200) NULL,
        [CLRDataTypeSqlServer] [varchar](2000) NULL,

     CONSTRAINT [PK_DbVsCSharpTypes] PRIMARY KEY CLUSTERED 
    (
        [DbVsCSharpTypesId] ASC
    )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
    ) ON [PRIMARY]

    GO


    SET NOCOUNT ON;
    SET XACT_ABORT ON;
    GO

    SET IDENTITY_INSERT [dbo].[DbVsCSharpTypes] ON;
    BEGIN TRANSACTION;
    INSERT INTO [dbo].[DbVsCSharpTypes]([DbVsCSharpTypesId], [Sql2008DataType], [CSharpDataType], [CLRDataType], [CLRDataTypeSqlServer])
    SELECT 1, N'bigint', N'long', N'Int64, Nullable<Int64>', N'SqlInt64' UNION ALL
    SELECT 2, N'binary', N'byte[]', N'Byte[]', N'SqlBytes, SqlBinary' UNION ALL
    SELECT 3, N'bit', N'bool', N'Boolean, Nullable<Boolean>', N'SqlBoolean' UNION ALL
    SELECT 4, N'char', N'char', NULL, NULL UNION ALL
    SELECT 5, N'cursor', NULL, NULL, NULL UNION ALL
    SELECT 6, N'date', N'DateTime', N'DateTime, Nullable<DateTime>', N'SqlDateTime' UNION ALL
    SELECT 7, N'datetime', N'DateTime', N'DateTime, Nullable<DateTime>', N'SqlDateTime' UNION ALL
    SELECT 8, N'datetime2', N'DateTime', N'DateTime, Nullable<DateTime>', N'SqlDateTime' UNION ALL
    SELECT 9, N'DATETIMEOFFSET', N'DateTimeOffset', N'DateTimeOffset', N'DateTimeOffset, Nullable<DateTimeOffset>' UNION ALL
    SELECT 10, N'decimal', N'decimal', N'Decimal, Nullable<Decimal>', N'SqlDecimal' UNION ALL
    SELECT 11, N'float', N'double', N'Double, Nullable<Double>', N'SqlDouble' UNION ALL
    SELECT 12, N'geography', NULL, NULL, N'SqlGeography is defined in Microsoft.SqlServer.Types.dll, which is installed with SQL Server and can be downloaded from the SQL Server 2008 feature pack.' UNION ALL
    SELECT 13, N'geometry', NULL, NULL, N'SqlGeometry is defined in Microsoft.SqlServer.Types.dll, which is installed with SQL Server and can be downloaded from the SQL Server 2008 feature pack.' UNION ALL
    SELECT 14, N'hierarchyid', NULL, NULL, N'SqlHierarchyId is defined in Microsoft.SqlServer.Types.dll, which is installed with SQL Server and can be downloaded from the SQL Server 2008 feature pack.' UNION ALL
    SELECT 15, N'image', NULL, NULL, NULL UNION ALL
    SELECT 16, N'int', N'int', N'Int32, Nullable<Int32>', N'SqlInt32' UNION ALL
    SELECT 17, N'money', N'decimal', N'Decimal, Nullable<Decimal>', N'SqlMoney' UNION ALL
    SELECT 18, N'nchar', N'string', N'String, Char[]', N'SqlChars, SqlString' UNION ALL
    SELECT 19, N'ntext', NULL, NULL, NULL UNION ALL
    SELECT 20, N'numeric', N'decimal', N'Decimal, Nullable<Decimal>', N'SqlDecimal' UNION ALL
    SELECT 21, N'nvarchar', N'string', N'String, Char[]', N'SqlChars, SqlStrinG SQLChars is a better match for data transfer and access, and SQLString is a better match for performing String operations.' UNION ALL
    SELECT 22, N'nvarchar(1), nchar(1)', N'string', N'Char, String, Char[], Nullable<char>', N'SqlChars, SqlString' UNION ALL
    SELECT 23, N'real', N'single', N'Single, Nullable<Single>', N'SqlSingle' UNION ALL
    SELECT 24, N'rowversion', N'byte[]', N'Byte[]', NULL UNION ALL
    SELECT 25, N'smallint', N'smallint', N'Int16, Nullable<Int16>', N'SqlInt16' UNION ALL
    SELECT 26, N'smallmoney', N'decimal', N'Decimal, Nullable<Decimal>', N'SqlMoney' UNION ALL
    SELECT 27, N'sql_variant', N'object', N'Object', NULL UNION ALL
    SELECT 28, N'table', NULL, NULL, NULL UNION ALL
    SELECT 29, N'text', N'string', NULL, NULL UNION ALL
    SELECT 30, N'time', N'TimeSpan', N'TimeSpan, Nullable<TimeSpan>', N'TimeSpan' UNION ALL
    SELECT 31, N'timestamp', NULL, NULL, NULL UNION ALL
    SELECT 32, N'tinyint', N'byte', N'Byte, Nullable<Byte>', N'SqlByte' UNION ALL
    SELECT 33, N'uniqueidentifier', N'Guid', N'Guid, Nullable<Guid>', N'SqlGuidUser-defined type(UDT)The same class that is bound to the user-defined type in the same assembly or a dependent assembly.' UNION ALL
    SELECT 34, N'varbinary ', N'byte[]', N'Byte[]', N'SqlBytes, SqlBinary' UNION ALL
    SELECT 35, N'varbinary(1), binary(1)', N'byte', N'byte, Byte[], Nullable<byte>', N'SqlBytes, SqlBinary' UNION ALL
    SELECT 36, N'varchar', NULL, NULL, NULL UNION ALL
    SELECT 37, N'xml', NULL, NULL, N'SqlXml'
    COMMIT;
    RAISERROR (N'[dbo].[DbVsCSharpTypes]: Insert Batch: 1.....Done!', 10, 1) WITH NOWAIT;
    GO

    SET IDENTITY_INSERT [dbo].[DbVsCSharpTypes] OFF;

#3

    internal Type type(SqlDbType sqltype)
    {
        Type resulttype = null;
        Dictionary<SqlDbType, Type> Types = new Dictionary<SqlDbType, Type>();
        Types.Add(SqlDbType.BigInt, typeof(Int64));
        Types.Add(SqlDbType.Binary, typeof(Byte[]));
        Types.Add(SqlDbType.Bit, typeof(Boolean));
        Types.Add(SqlDbType.Char, typeof(String));
        Types.Add(SqlDbType.Date, typeof(DateTime));
        Types.Add(SqlDbType.DateTime, typeof(DateTime));
        Types.Add(SqlDbType.DateTime2, typeof(DateTime));
        Types.Add(SqlDbType.DateTimeOffset, typeof(DateTimeOffset));
        Types.Add(SqlDbType.Decimal, typeof(Decimal));
        Types.Add(SqlDbType.Float, typeof(Double));
        Types.Add(SqlDbType.Image, typeof(Byte[]));
        Types.Add(SqlDbType.Int, typeof(Int32));
        Types.Add(SqlDbType.Money, typeof(Decimal));
        Types.Add(SqlDbType.NChar, typeof(String));
        Types.Add(SqlDbType.NText, typeof(String));
        Types.Add(SqlDbType.NVarChar, typeof(String));
        Types.Add(SqlDbType.Real, typeof(Single));
        Types.Add(SqlDbType.SmallDateTime, typeof(DateTime));
        Types.Add(SqlDbType.SmallInt, typeof(Int16));
        Types.Add(SqlDbType.SmallMoney, typeof(Decimal));
        Types.Add(SqlDbType.Text, typeof(String));
        Types.Add(SqlDbType.Time, typeof(TimeSpan));
        Types.Add(SqlDbType.Timestamp, typeof(Byte[]));
        Types.Add(SqlDbType.TinyInt, typeof(Byte));
        Types.Add(SqlDbType.UniqueIdentifier, typeof(Guid));
        Types.Add(SqlDbType.VarBinary, typeof(Byte[]));
        Types.Add(SqlDbType.VarChar, typeof(String));
        Types.TryGetValue(sqltype, out resulttype);
        return resulttype;
    }

    internal SqlDbType type(Type systype)
    {
        SqlDbType resulttype = SqlDbType.NVarChar;
        Dictionary<Type, SqlDbType> Types = new Dictionary<Type, SqlDbType>();
        Types.Add(typeof(Boolean), SqlDbType.Bit);
        Types.Add(typeof(String), SqlDbType.NVarChar);
        Types.Add(typeof(DateTime), SqlDbType.DateTime);
        Types.Add(typeof(Int16), SqlDbType.Int);
        Types.Add(typeof(Int32), SqlDbType.Int);
        Types.Add(typeof(Int64), SqlDbType.Int);
        Types.Add(typeof(Decimal), SqlDbType.Float);
        Types.Add(typeof(Double), SqlDbType.Float);
        Types.TryGetValue(systype, out resulttype);
        return resulttype;
    }

#4

You don't need a function.I think you may be looking for

你不需要一个功能。我想你可能正在寻找

dt.Columns[i].DataType.UnderlyingSystemType

dt - dataTable

dt - dataTable

This will return the CLR type for corresponding column. Hope this helps and BTW this is my first answer on stack overflow

这将返回相应列的CLR类型。希望这会有所帮助,顺便说一下这是我关于堆栈溢出的第一个答案

#5

This doesn't directly answer the question as asked, but it does answer a common related one. Once you have an IDataReader you can call IDataRecord.GetFieldType(int) to "[get] the Type information corresponding to the type of Object that would be returned from GetValue."

这不会直接回答问题,但它确实回答了一个常见的相关问题。一旦有了IDataReader,就可以调用IDataRecord.GetFieldType(int)来“[获取]与GetValue返回的Object类型相对应的Type信息。”

#6

I include this extension (you could easily exchange the string key in the dictionary for SqlDbType as Greg has implemented - or even support both) in my model and expose a property that converts the CLR Type:

我包含了这个扩展(您可以轻松地在字典中为SqlDbType交换字符串键,因为Greg已经实现了 - 甚至支持两者)并且公开了一个转换CLR类型的属性:

    namespace X.Domain.Model
    {
        using System;
        using System.Collections.Generic;
        using System.Linq;
        using System.Text;
        public class StoredProcedureParameter : DomainObject
        {
            public StoredProcedureParameter() { }

            public string StoredProcedure { get; set; }

            public string ProcedureSchema { get; set; }

            public string ProcedureName { get; set; }

            public string ParameterName { get; set; }

            public string ParameterOrder { get; set; }

            public string ParameterMode { get; set; }

            public string SqlDataType { get; set; }

            public Type DataType { get { return this.SqlDataType.ToClrType(); } }
        }

        static class StoredProcedureParameterExtensions
        {
            private static Dictionary<string, Type> Mappings;
            public static StoredProcedureParameterExtensions()
            {
                Mappings = new Dictionary<string, Type>();
                Mappings.Add("bigint", typeof(Int64));
                Mappings.Add("binary", typeof(Byte[]));
                Mappings.Add("bit", typeof(Boolean));
                Mappings.Add("char", typeof(String));
                Mappings.Add("date", typeof(DateTime));
                Mappings.Add("datetime", typeof(DateTime));
                Mappings.Add("datetime2", typeof(DateTime));
                Mappings.Add("datetimeoffset", typeof(DateTimeOffset));
                Mappings.Add("decimal", typeof(Decimal));
                Mappings.Add("float", typeof(Double));
                Mappings.Add("image", typeof(Byte[]));
                Mappings.Add("int", typeof(Int32));
                Mappings.Add("money", typeof(Decimal));
                Mappings.Add("nchar", typeof(String));
                Mappings.Add("ntext", typeof(String));
                Mappings.Add("numeric", typeof(Decimal));
                Mappings.Add("nvarchar", typeof(String));
                Mappings.Add("real", typeof(Single));
                Mappings.Add("rowversion", typeof(Byte[]));
                Mappings.Add("smalldatetime", typeof(DateTime));
                Mappings.Add("smallint", typeof(Int16));
                Mappings.Add("smallmoney", typeof(Decimal));
                Mappings.Add("text", typeof(String));
                Mappings.Add("time", typeof(TimeSpan));
                Mappings.Add("timestamp", typeof(Byte[]));
                Mappings.Add("tinyint", typeof(Byte));
                Mappings.Add("uniqueidentifier", typeof(Guid));
                Mappings.Add("varbinary", typeof(Byte[]));
                Mappings.Add("varchar", typeof(String));

            }

            public static Type ToClrType(this string sqlType)
            {
                Type datatype = null;
                if (Mappings.TryGetValue(sqlType, out datatype))
                    return datatype;
                throw new TypeLoadException(string.Format("Can not load CLR Type from {0}", sqlType));
            }
        }
    }

#7

Here's a revision that accepts nullable.

这是一个接受可空的修订版。

    public static Type GetClrType(SqlDbType sqlType, bool isNullable)
    {
        switch (sqlType)
        {
            case SqlDbType.BigInt:
                return isNullable ? typeof(long?) : typeof(long);

            case SqlDbType.Binary:
            case SqlDbType.Image:
            case SqlDbType.Timestamp:
            case SqlDbType.VarBinary:
                return typeof(byte[]);

            case SqlDbType.Bit:
                return isNullable ? typeof(bool?) : typeof(bool);

            case SqlDbType.Char:
            case SqlDbType.NChar:
            case SqlDbType.NText:
            case SqlDbType.NVarChar:
            case SqlDbType.Text:
            case SqlDbType.VarChar:
            case SqlDbType.Xml:
                return typeof(string);

            case SqlDbType.DateTime:
            case SqlDbType.SmallDateTime:
            case SqlDbType.Date:
            case SqlDbType.Time:
            case SqlDbType.DateTime2:
                return isNullable ? typeof(DateTime?) : typeof(DateTime);

            case SqlDbType.Decimal:
            case SqlDbType.Money:
            case SqlDbType.SmallMoney:
                return isNullable ? typeof(decimal?) : typeof(decimal);

            case SqlDbType.Float:
                return isNullable ? typeof(double?) : typeof(double);

            case SqlDbType.Int:
                return isNullable ? typeof(int?) : typeof(int);

            case SqlDbType.Real:
                return isNullable ? typeof(float?) : typeof(float);

            case SqlDbType.UniqueIdentifier:
                return isNullable ? typeof(Guid?) : typeof(Guid);

            case SqlDbType.SmallInt:
                return isNullable ? typeof(short?) : typeof(short);

            case SqlDbType.TinyInt:
                return isNullable ? typeof(byte?) : typeof(byte);

            case SqlDbType.Variant:
            case SqlDbType.Udt:
                return typeof(object);

            case SqlDbType.Structured:
                return typeof(DataTable);

            case SqlDbType.DateTimeOffset:
                return isNullable ? typeof(DateTimeOffset?) : typeof(DateTimeOffset);

            default:
                throw new ArgumentOutOfRangeException("sqlType");
        }
    }

#8

You can try Wizardby. However, it maps from so-called "native" data types to DbType, which are then trivial to convert to CLR types. If this fits, you'll need an appropriate IDbTypeMapper - either SqlServer2000TypeMapper or SqlServer2005TypeMapper.

你可以试试Wizardby。但是,它从所谓的“本机”数据类型映射到DbType,然后转换为CLR类型是微不足道的。如果这适合,您将需要一个合适的IDbTypeMapper - SqlServer2000TypeMapper或SqlServer2005TypeMapper。

#9

I think there is no built in for that, but you can use VS to generate classes for your tables and then try to edit them

我认为没有内置功能,但您可以使用VS为表生成类,然后尝试编辑它们

#10

Why not create a typed dataset and have the VS designer do the mapping for you? Unless the project has to adapt at runtime to different schemas, then you should use code generation techniques to create your classes, wether the built-in designers (ie. typed datasets) or custom ones (schema->XML->XSLT->.cs).

为什么不创建一个类型化数据集并让VS设计师为您做映射?除非项目必须在运行时适应不同的模式,否则您应该使用代码生成技术来创建类,内置设计器(即类型化数据集)或自定义设计器(模式 - > XML-> XSLT->。 CS)。

#11

Normally I just use the Value property to convert a SqlType to a native .NET type. This does the job most of the time. If I have a corner case, I'll just write a quick helper function.

通常我只使用Value属性将SqlType转换为本机.NET类型。这在大多数时间都可以完成。如果我有一个角落案例,我会写一个快速帮助函数。

int i = dataReader.GetSqlInt32(0).Value;

#12

I understand that you're discussing writing a switch statement, but here's an alternate for Sql Server (similar concepts work for other DBs)

我知道你正在讨论编写一个switch语句,但这里是Sql Server的替代品(类似的概念适用于其他DB)

Consider using SysObjects to retrieve the full data types and generate your class:

考虑使用SysObjects检索完整数据类型并生成您的类:

declare @ProcName varchar(255)
select @ProcName='Table, View, or Proc'
SELECT --DISTINCT 
    b.name 
    , c.name Type
    , b.xtype
    , b.length 
    , b.isoutparam
FROM 
    sysObjects a 
INNER JOIN sysCOLUMNs b ON a.id=b.id 
INNER JOIN systypes c ON b.xtype=c.xtype  
WHERE 
    a.name=@ProcName
order by b.colorder

Now you're just enumerating a DataTable instead of the longer statement.

现在你只是枚举一个DataTable而不是更长的语句。