[英]C# Equivalent of SQL Server DataTypes
对于以下 SQL Server 数据类型,C# 中对应的数据类型是什么?
精确数字
bigint
numeric
bit
smallint
decimal
smallmoney
int
tinyint
money
近似数字
float
real
日期和时间
date
datetimeoffset
datetime2
smalldatetime
datetime
time
字符串
char
varchar
text
Unicode 字符串
nchar
nvarchar
ntext
二进制字符串
binary
varbinary
image
其他数据类型
cursor
timestamp
hierarchyid
uniqueidentifier
sql_variant
xml
table
(来源: MSDN )
这是针对SQL Server 2005 的。 SQL Server 2008 、 SQL Server 2008 R2 、 SQL Server 2012和SQL Server 2014的表有更新版本。
下表列出了 Microsoft SQL Server 数据类型、它们在System.Data.SqlTypes命名空间中 SQL Server 的公共语言运行时 (CLR) 中的等效项,以及它们在 Microsoft .NET Framework 中的本机 CLR 等效项。
SQL Server data type CLR data type (SQL Server) CLR data type (.NET Framework)
varbinary SqlBytes, SqlBinary Byte[]
binary SqlBytes, SqlBinary Byte[]
varbinary(1), binary(1) SqlBytes, SqlBinary byte, Byte[]
image None None
varchar None None
char None None
nvarchar(1), nchar(1) SqlChars, SqlString Char, String, Char[]
nvarchar SqlChars, SqlString String, Char[]
nchar SqlChars, SqlString String, Char[]
text None None
ntext None None
uniqueidentifier SqlGuid Guid
rowversion None Byte[]
bit SqlBoolean Boolean
tinyint SqlByte Byte
smallint SqlInt16 Int16
int SqlInt32 Int32
bigint SqlInt64 Int64
smallmoney SqlMoney Decimal
money SqlMoney Decimal
numeric SqlDecimal Decimal
decimal SqlDecimal Decimal
real SqlSingle Single
float SqlDouble Double
smalldatetime SqlDateTime DateTime
datetime SqlDateTime DateTime
sql_variant None Object
User-defined type(UDT) None user-defined type
table None None
cursor None None
timestamp None None
xml SqlXml None
如果有人正在寻找从/向 C# 和 SQL Server 格式转换的方法,这里有一个简单的实现:
private readonly string[] SqlServerTypes = { "bigint", "binary", "bit", "char", "date", "datetime", "datetime2", "datetimeoffset", "decimal", "filestream", "float", "geography", "geometry", "hierarchyid", "image", "int", "money", "nchar", "ntext", "numeric", "nvarchar", "real", "rowversion", "smalldatetime", "smallint", "smallmoney", "sql_variant", "text", "time", "timestamp", "tinyint", "uniqueidentifier", "varbinary", "varchar", "xml" };
private readonly string[] CSharpTypes = { "long", "byte[]", "bool", "char", "DateTime", "DateTime", "DateTime", "DateTimeOffset", "decimal", "byte[]", "double", "Microsoft.SqlServer.Types.SqlGeography", "Microsoft.SqlServer.Types.SqlGeometry", "Microsoft.SqlServer.Types.SqlHierarchyId", "byte[]", "int", "decimal", "string", "string", "decimal", "string", "Single", "byte[]", "DateTime", "short", "decimal", "object", "string", "TimeSpan", "byte[]", "byte", "Guid", "byte[]", "string", "string" };
public string ConvertSqlServerFormatToCSharp(string typeName)
{
var index = Array.IndexOf(SqlServerTypes, typeName);
return index > -1
? CSharpTypes[index]
: "object";
}
public string ConvertCSharpFormatToSqlServer(string typeName)
{
var index = Array.IndexOf(CSharpTypes, typeName);
return index > -1
? SqlServerTypes[index]
: null;
}
编辑:修正错别字
SQL Server 和 .NET Framework 基于不同的类型系统。 例如,.NET Framework Decimal 结构的最大小数位数为 28,而 SQL Server 小数和数字数据类型的最大小数位数为 38。单击此处的链接! 详情
https://msdn.microsoft.com/en-us/library/cc716729(v=vs.110).aspx
public static string FromSqlType(string sqlTypeString)
{
if (! Enum.TryParse(sqlTypeString, out Enums.SQLType typeCode))
{
throw new Exception("sql type not found");
}
switch (typeCode)
{
case Enums.SQLType.varbinary:
case Enums.SQLType.binary:
case Enums.SQLType.filestream:
case Enums.SQLType.image:
case Enums.SQLType.rowversion:
case Enums.SQLType.timestamp://?
return "byte[]";
case Enums.SQLType.tinyint:
return "byte";
case Enums.SQLType.varchar:
case Enums.SQLType.nvarchar:
case Enums.SQLType.nchar:
case Enums.SQLType.text:
case Enums.SQLType.ntext:
case Enums.SQLType.xml:
return "string";
case Enums.SQLType.@char:
return "char";
case Enums.SQLType.bigint:
return "long";
case Enums.SQLType.bit:
return "bool";
case Enums.SQLType.smalldatetime:
case Enums.SQLType.datetime:
case Enums.SQLType.date:
case Enums.SQLType.datetime2:
return "DateTime";
case Enums.SQLType.datetimeoffset:
return "DateTimeOffset";
case Enums.SQLType.@decimal:
case Enums.SQLType.money:
case Enums.SQLType.numeric:
case Enums.SQLType.smallmoney:
return "decimal";
case Enums.SQLType.@float:
return "double";
case Enums.SQLType.@int:
return "int";
case Enums.SQLType.real:
return "Single";
case Enums.SQLType.smallint:
return "short";
case Enums.SQLType.uniqueidentifier:
return "Guid";
case Enums.SQLType.sql_variant:
return "object";
case Enums.SQLType.time:
return "TimeSpan";
default:
throw new Exception("none equal type");
}
}
public enum SQLType
{
varbinary,//(1)
binary,//(1)
image,
varchar,
@char,
nvarchar,//(1)
nchar,//(1)
text,
ntext,
uniqueidentifier,
rowversion,
bit,
tinyint,
smallint,
@int,
bigint,
smallmoney,
money,
numeric,
@decimal,
real,
@float,
smalldatetime,
datetime,
sql_variant,
table,
cursor,
timestamp,
xml,
date,
datetime2,
datetimeoffset,
filestream,
time,
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.