System.Data.DbType 到 TSQL 参数数据类型答案

【问题标题】：System.Data.DbType to TSQL parameter datatypeSystem.Data.DbType 到 TSQL 参数数据类型
【发布时间】：2014-06-03 17:43:03
【问题描述】：

你们是否知道映射列表或理想情况下的 .NET 标准类或函数，它们会将 System.Data.DbType 枚举选项转换为与指定 SQL Server 类型对应的 TSQL“字符串”。

// Type: System.Data.DbType
// Assembly: System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
// MVID: CB77DBFA-81C4-4326-93F6-E2EEC5D3C28A
// Assembly location: C:\Windows\Microsoft.NET\Framework\v4.0.30319\System.Data.dll

    namespace System.Data
    {
      /// <summary>
      /// Specifies the data type of a field, a property, or a Parameter object of a .NET Framework data provider.
      /// </summary>
      /// <filterpriority>2</filterpriority>
      public enum DbType
      {
        AnsiString = 0,
        Binary = 1,
        Byte = 2,
        Boolean = 3,
        Currency = 4,
        Date = 5,
        DateTime = 6,
        Decimal = 7,
        Double = 8,
        Guid = 9,
        Int16 = 10,
        Int32 = 11,
        Int64 = 12,
        Object = 13,
        SByte = 14,
        Single = 15,
        String = 16,
        Time = 17,
        UInt16 = 18,
        UInt32 = 19,
        UInt64 = 20,
        VarNumeric = 21,
        AnsiStringFixedLength = 22,
        StringFixedLength = 23,
        Xml = 25,
        DateTime2 = 26,
        DateTimeOffset = 27,
      }
    }

例子：

DbType.Int32 -> INT
DbType.AnsiString -> VARCHAR
DbType.String -> NVARCHAR
DbType.Guid -> UNIQUEIDENTIFIER

感谢您的帮助。

【问题讨论】：

只需创建一个字典
我需要知道什么 DbType 映射到什么 SQL 类型，以便创建正是我所要求的字典:)
您无法从文档中弄清楚这一点？ msdn.microsoft.com/en-us/library/…msdn.microsoft.com/en-us/library/ms187752.aspx
msdn.microsoft.com/en-us/library/cc716729(v=vs.110).aspx

标签： sql .net sql-server tsql c#-4.0

【解决方案1】：

我不记得我从哪里得到的，但我会发布它以供将来参考。

namespace CodeInsiders.SharpQL
{
    using System;
    using System.Collections.Generic;
    using System.Data;
   
    public static class SqlMapper
    {
        private static readonly Dictionary<DbType, Type> DbTypeMapToNullableType = new Dictionary<DbType, Type>
        {
            { DbType.Byte, typeof(byte?) },
            { DbType.SByte, typeof(sbyte?) },
            { DbType.Int16, typeof(short?) },
            { DbType.UInt16, typeof(ushort?) },
            { DbType.Int32, typeof(int?) },
            { DbType.UInt32, typeof(uint?) },
            { DbType.Int64, typeof(long?) },
            { DbType.UInt64, typeof(ulong?) },
            { DbType.Single, typeof(float?) },
            { DbType.Double, typeof(double?) },
            { DbType.Decimal, typeof(decimal?) },
            { DbType.Boolean, typeof(bool?) },
            { DbType.StringFixedLength, typeof(char?) },
            { DbType.Guid, typeof(Guid?) },
            { DbType.DateTime, typeof(DateTime?) },
            { DbType.DateTimeOffset, typeof(DateTimeOffset?) },
            { DbType.Binary, typeof(byte[]) }
        };
   
        private static readonly Dictionary<DbType, Type> DbTypeMapToType = new Dictionary<DbType, Type>
        {
            { DbType.Byte, typeof(byte) },
            { DbType.SByte, typeof(sbyte) },
            { DbType.Int16, typeof(short) },
            { DbType.UInt16, typeof(ushort) },
            { DbType.Int32, typeof(int) },
            { DbType.UInt32, typeof(uint) },
            { DbType.Int64, typeof(long) },
            { DbType.UInt64, typeof(ulong) },
            { DbType.Single, typeof(float) },
            { DbType.Double, typeof(double) },
            { DbType.Decimal, typeof(decimal) },
            { DbType.Boolean, typeof(bool) },
            { DbType.String, typeof(string) },
            { DbType.StringFixedLength, typeof(char) },
            { DbType.Guid, typeof(Guid) },
            { DbType.DateTime, typeof(DateTime) },
            { DbType.DateTimeOffset, typeof(DateTimeOffset) },
            { DbType.Binary, typeof(byte[]) }
        };
    
        private static readonly Dictionary<SqlDbType, Type> SqlDbTypeToNullableType = new Dictionary<SqlDbType, Type>
        {
            { SqlDbType.BigInt, typeof(long?) },
            { SqlDbType.Binary, typeof(byte[]) },
            { SqlDbType.Image, typeof(byte[]) },
            { SqlDbType.Timestamp, typeof(byte[]) },
            { SqlDbType.VarBinary, typeof(byte[]) },
            { SqlDbType.Bit, typeof(bool?) },
            { SqlDbType.Char, typeof(string) },
            { SqlDbType.NChar, typeof(string) },
            { SqlDbType.NText, typeof(string) },
            { SqlDbType.NVarChar, typeof(string) },
            { SqlDbType.Text, typeof(string) },
            { SqlDbType.VarChar, typeof(string) },
            { SqlDbType.Xml, typeof(string) },
            { SqlDbType.DateTime, typeof(DateTime?) },
            { SqlDbType.SmallDateTime, typeof(DateTime?) },
            { SqlDbType.Date, typeof(DateTime?) },
            { SqlDbType.Time, typeof(DateTime?) },
            { SqlDbType.DateTime2, typeof(DateTime?) },
            { SqlDbType.Decimal, typeof(decimal?) },
            { SqlDbType.Money, typeof(decimal?) },
            { SqlDbType.SmallMoney, typeof(decimal?) },
            { SqlDbType.Float, typeof(double?) },
            { SqlDbType.Int, typeof(int?) },
            { SqlDbType.Real, typeof(float?) },
            { SqlDbType.UniqueIdentifier, typeof(Guid?) },
            { SqlDbType.SmallInt, typeof(short?) },
            { SqlDbType.TinyInt, typeof(byte?) },
            { SqlDbType.Variant, typeof(object) },
            { SqlDbType.Udt, typeof(object) },
            { SqlDbType.Structured, typeof(DataTable) },
            { SqlDbType.DateTimeOffset, typeof(DateTimeOffset) }
        };
    
        private static readonly Dictionary<SqlDbType, Type> SqlDbTypeToType = new Dictionary<SqlDbType, Type>
        {
            { SqlDbType.BigInt, typeof(long) },
            { SqlDbType.Binary, typeof(byte[]) },
            { SqlDbType.Image, typeof(byte[]) },
            { SqlDbType.Timestamp, typeof(byte[]) },
            { SqlDbType.VarBinary, typeof(byte[]) },
            { SqlDbType.Bit, typeof(bool) },
            { SqlDbType.Char, typeof(string) },
            { SqlDbType.NChar, typeof(string) },
            { SqlDbType.NText, typeof(string) },
            { SqlDbType.NVarChar, typeof(string) },
            { SqlDbType.Text, typeof(string) },
            { SqlDbType.VarChar, typeof(string) },
            { SqlDbType.Xml, typeof(string) },
            { SqlDbType.DateTime, typeof(DateTime) },
            { SqlDbType.SmallDateTime, typeof(DateTime) },
            { SqlDbType.Date, typeof(DateTime) },
            { SqlDbType.Time, typeof(DateTime) },
            { SqlDbType.DateTime2, typeof(DateTime) },
            { SqlDbType.Decimal, typeof(decimal) },
            { SqlDbType.Money, typeof(decimal) },
            { SqlDbType.SmallMoney, typeof(decimal) },
            { SqlDbType.Float, typeof(double) },
            { SqlDbType.Int, typeof(int) },
            { SqlDbType.Real, typeof(float) },
            { SqlDbType.UniqueIdentifier, typeof(Guid) },
            { SqlDbType.SmallInt, typeof(short) },
            { SqlDbType.TinyInt, typeof(byte) },
            { SqlDbType.Variant, typeof(object) },
            { SqlDbType.Udt, typeof(object) },
            { SqlDbType.Structured, typeof(DataTable) },
            { SqlDbType.DateTimeOffset, typeof(DateTimeOffset) }
        };
    
        private static readonly Dictionary<Type, DbType> TypeToDbType = new Dictionary<Type, DbType>
        {
            { typeof(byte), DbType.Byte },
            { typeof(sbyte), DbType.SByte },
            { typeof(short), DbType.Int16 },
            { typeof(ushort), DbType.UInt16 },
            { typeof(int), DbType.Int32 },
            { typeof(uint), DbType.UInt32 },
            { typeof(long), DbType.Int64 },
            { typeof(ulong), DbType.UInt64 },
            { typeof(float), DbType.Single },
            { typeof(double), DbType.Double },
            { typeof(decimal), DbType.Decimal },
            { typeof(bool), DbType.Boolean },
            { typeof(string), DbType.String },
            { typeof(char), DbType.StringFixedLength },
            { typeof(Guid), DbType.Guid },
            { typeof(DateTime), DbType.DateTime },
            {
                typeof(DateTimeOffset),
                DbType.DateTimeOffset
            },
            { typeof(byte[]), DbType.Binary },
            { typeof(byte?), DbType.Byte },
            { typeof(sbyte?), DbType.SByte },
            { typeof(short?), DbType.Int16 },
            { typeof(ushort?), DbType.UInt16 },
            { typeof(int?), DbType.Int32 },
            { typeof(uint?), DbType.UInt32 },
            { typeof(long?), DbType.Int64 },
            { typeof(ulong?), DbType.UInt64 },
            { typeof(float?), DbType.Single },
            { typeof(double?), DbType.Double },
            { typeof(decimal?), DbType.Decimal },
            { typeof(bool?), DbType.Boolean },
            { typeof(char?), DbType.StringFixedLength },
            { typeof(Guid?), DbType.Guid },
            { typeof(DateTime?), DbType.DateTime },
            {
                typeof(DateTimeOffset?),
                DbType.DateTimeOffset
            },
        };
    
        public static Type ToClrType(this DbType dbType) {
            Type type;
            if (DbTypeMapToType.TryGetValue(dbType, out type)) {
                return type;
            }
        
            throw new ArgumentOutOfRangeException("dbType", dbType, "Cannot map the DbType to Type");
        }
        
        public static Type ToClrType(this SqlDbType sqlDbType) {
            Type type;
            if (SqlDbTypeToType.TryGetValue(sqlDbType, out type)) {
                return type;
            }
        
            throw new ArgumentOutOfRangeException("sqlDbType", sqlDbType, "Cannot map the SqlDbType to Type");
        }
        
        public static DbType ToDbType(this Type type) {
            DbType dbType;
            if (TypeToDbType.TryGetValue(type, out dbType)) {
                return dbType;
            }
        
            throw new ArgumentOutOfRangeException("type", type, "Cannot map the Type to DbType");
        }
        
        public static Type ToNullableClrType(this DbType dbType) {
            Type type;
            if (DbTypeMapToNullableType.TryGetValue(dbType, out type)) {
                return type;
            }
        
            throw new ArgumentOutOfRangeException("dbType", dbType, "Cannot map the DbType to Nullable Type");
        }
        
        public static Type ToNullableClrType(this SqlDbType sqlDbType) {
            Type type;
            if (SqlDbTypeToNullableType.TryGetValue(sqlDbType, out type)) {
                return type;
            }
        
            throw new ArgumentOutOfRangeException("sqlDbType", sqlDbType, "Cannot map the SqlDbType to Nullable Type");
        }
    }
}

【讨论】：

【解决方案2】：

这里是我之前写的几行代码：

 public enum Recurring_DayOfWeek
  {
    Sunday = 2,
    Monday = 4,
    Tuesday = 8,
    Wednesday = 16,
    Thursday = 32,
    Friday = 64,
    Saturday = 128
  }

Req_Param 是 Enum 的描述，但如果你没有描述将起作用，我在 EnumHelper 中留下示例......

     System.Data.SqlDbType sqlDatatype =     (System.Data.SqlDbType)Enum.Parse(typeof(System.Data.SqlDbType),     EnumHelper.EnumDescription(Req_Param), true);




using System.ComponentModel;
 public static class EnumHelper
{

    public enum Speed
    {
        [Description("5 metters per second")]
        Five = 5,
        [Description("10 metters per second")]
        Ten = 10,
        [Description("15 metters per second")]
        Fifteen = 15,
        [Description("20 metters per second")]
        Twenty = 20,
        //[Description("25 metters per second")]
        TwentyFive = 25,
       [Description("30 metters per second")]
        Thirty = 30
    }

    /// <summary>
    /// get the string value of Enum Attribute
    /// </summary>
    /// <param name="EnumConstant"></param>
    /// <returns>
    /// string enumDesctiption = EnumHelper.EnumDescription(EnumHelper.Speed.Thirty);
    ///  enumDesctiption = EnumHelper.EnumDescription(DayOfWeek.Monday); when there is no desc returns as string the ENUM property
    /// </returns>
    public static string EnumDescription(Enum EnumConstant)
    {
        System.Reflection.FieldInfo fi = EnumConstant.GetType().GetField(EnumConstant.ToString());
        DescriptionAttribute[] aattr = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
        if (aattr.Length > 0)
        {
          return aattr[0].Description;
        }
        else
        {
            return EnumConstant.ToString();
        }
    }



}

小心 BIT 和验证 C#、VB.NET SQL

【讨论】：