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

我只是想表达我的意见

0) QueryFirst https://marketplace.visualstudio.com/items?itemName=bbsimonbb.QueryFirst Query-first is a visual studio extension for working intelligently with SQL in C# projects. Use the provided .sql template to develop your queries. When you save the file, Query-first runs your query, retrieves the schema and generates two classes and an interface: a wrapper class with methods Execute(), ExecuteScalar(), ExecuteNonQuery() etc, its corresponding interface, and a POCO encapsulating a line of results.

1) Sql2Objects 从查询结果开始创建类(但不是DAL)

2) https://learn.microsoft.com/en-us/ef/ef6/resources/tools

3) https://visualstudiomagazine.com/articles/2012/12/11/sqlqueryresults-code-generation.aspx

4) http://www.codesmithtools.com/product/generator#features

其他回答

我尝试过node.js,它对我来说工作得很好。

它将为您创建模型文件。您可以创建多个模型文件

前提条件:安装node.js

需要更改:

在你的工作区中创建index.js文件 在“allTable”中添加你的tables对象(截图中高亮显示) 更改文件夹路径(我已经给出了我的系统路径) 执行命令节点index.js

节点index.js

输出

const fs = require('fs/promises'); async function convertToDataType(dataArray, fileName) { let count = 0; let tempArray = []; var dataTypeArray = [ { "key": "bigint", "value": "long" }, { "key": "binary", "value": "byte[]" }, { "key": "bit", "value": "bool" }, { "key": "char", "value": "string" }, { "key": "date", "value": "DateTime" }, { "key": "datetime", "value": "DateTime" }, { "key": "datetime2", "value": "DateTime" }, { "key": "datetimeoffset", "value": "DateTimeOffset" }, { "key": "decimal", "value": "decimal" }, { "key": "float", "value": "double" }, { "key": "image", "value": "byte[]" }, { "key": "int", "value": "int" }, { "key": "money", "value": "decimal" }, { "key": "nchar", "value": "string" }, { "key": "ntext", "value": "string" }, { "key": "numeric", "value": "decimal" }, { "key": "nvarchar", "value": "string" }, { "key": "real", "value": "float" }, { "key": "smalldatetime", "value": "DateTime" }, { "key": "smallint", "value": "short" }, { "key": "smallmoney", "value": "decimal" }, { "key": "text", "value": "string" }, { "key": "time", "value": "TimeSpan" }, { "key": "timestamp", "value": "long" }, { "key": "tinyint", "value": "byte" }, { "key": "uniqueidentifier", "value": "Guid" }, { "key": "varbinary", "value": "byte[]" }, { "key": "varchar", "value": "string" } ] dataArray.map(i => { let objDataType = ''; objDataType = dataTypeArray.filter(data => data.key == i.split(' ')[1].replace('[', '').replace(']', ''))[0].value; if (objDataType == '') { count++; } let isNull = i.includes('NULL') && !(i.includes('varchar') || i.includes('bit')) ? '?' : ''; isNull = i.includes('NOT NULL') ? '' : isNull; const varValue = i.split(' ')[0].replace('[', '').replace(']', ''); if (count != 0) { console.warn(`\n\n\n ======> Error:: Check data type is missing. Datatype => ${i.split(' ')[1]} Object Name: ${fileName} \n\n\n`); } else { tempArray.push(`public ${objDataType}${isNull} ${varValue} { get; set; }`); } }); return tempArray; } async function convertToModel() { try { let allTable = { EmployeeAllowancesHistory: [ "[EmployeeAllowanceHistoryID] [int] NOT NULL", "[EmployeeID] [int] NOT NULL", "[AllowanceID] [int] NOT NULL", "[DateID] [int] NULL", "[Amount] [numeric] NOT NULL", "[Insured] [bit] NULL", "[ChangeDate] [datetime] NOT NULL", "[NewAmount] [numeric] NULL" ], Cities: [ "[CityID] [int] NOT NULL", "[CityCode] [varchar] NOT NULL", "[CityNameAr] [varchar] NULL", "[CityNameEn] [varchar] NULL", "[InKSA] [bit] NOT NULL", "[HighClass] [bit] NOT NULL", "[TravelDays] [int] NULL" ], Regions: [ "[RegionID] [int] NOT NULL", "[RegionCode] [nvarchar] NULL", "[RegionNameEn] [nvarchar] NULL", "[RegionNameAr] [nvarchar] NULL", "[CityID] [int] NULL" ] } for (var file in allTable) { const tableObject = await convertToDataType(allTable[file], file); let tempContent = "[key]"; tableObject.map(obj => { tempContent = `${tempContent} ${obj}` }); const content = `using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; namespace Core.Entities { public class ${file} { ${tempContent} } }` fs.writeFile(`/model_files/${file}.cs`, content); } console.log('Created successfully...'); } catch (err) { console.log(err); } } convertToModel();

我无法让亚历克斯的答案在Sql Server 2008 R2上工作。所以,我用同样的基本原理重写了它。它现在支持模式,并且对列属性映射(包括将可为空的日期类型映射为可为空的c#值类型)进行了一些修复。下面是Sql语句:

   DECLARE @TableName VARCHAR(MAX) = 'NewsItem' -- Replace 'NewsItem' with your table name
    DECLARE @TableSchema VARCHAR(MAX) = 'Markets' -- Replace 'Markets' with your schema name
    DECLARE @result varchar(max) = ''

    SET @result = @result + 'using System;' + CHAR(13) + CHAR(13) 

    IF (@TableSchema IS NOT NULL) 
    BEGIN
        SET @result = @result + 'namespace ' + @TableSchema  + CHAR(13) + '{' + CHAR(13) 
    END

    SET @result = @result + 'public class ' + @TableName + CHAR(13) + '{' + CHAR(13) 

    SET @result = @result + '#region Instance Properties' + CHAR(13)  

   SELECT
      @result = @result + CHAR(13)
      + ' public ' + ColumnType + ' ' + ColumnName + ' { get; set; } ' + CHAR(13)
    FROM (SELECT
      c.COLUMN_NAME AS ColumnName,
      CASE c.DATA_TYPE
        WHEN 'bigint' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Int64?'
            ELSE 'Int64'
          END
        WHEN 'binary' THEN 'Byte[]'
        WHEN 'bit' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'bool?'
            ELSE 'bool'
          END
        WHEN 'char' THEN 'string'
        WHEN 'date' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'DateTime?'
            ELSE 'DateTime'
          END
        WHEN 'datetime' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'DateTime?'
            ELSE 'DateTime'
          END
        WHEN 'datetime2' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'DateTime?'
            ELSE 'DateTime'
          END
        WHEN 'datetimeoffset' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'DateTimeOffset?'
            ELSE 'DateTimeOffset'
          END
        WHEN 'decimal' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'decimal?'
            ELSE 'decimal'
          END
        WHEN 'float' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Single?'
            ELSE 'Single'
          END
        WHEN 'image' THEN 'Byte[]'
        WHEN 'int' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'int?'
            ELSE 'int'
          END
        WHEN 'money' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'decimal?'
            ELSE 'decimal'
          END
        WHEN 'nchar' THEN 'string'
        WHEN 'ntext' THEN 'string'
        WHEN 'numeric' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'decimal?'
            ELSE 'decimal'
          END
        WHEN 'nvarchar' THEN 'string'
        WHEN 'real' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Double?'
            ELSE 'Double'
          END
        WHEN 'smalldatetime' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'DateTime?'
            ELSE 'DateTime'
          END
        WHEN 'smallint' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Int16?'
            ELSE 'Int16'
          END
        WHEN 'smallmoney' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'decimal?'
            ELSE 'decimal'
          END
        WHEN 'text' THEN 'string'
        WHEN 'time' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'TimeSpan?'
            ELSE 'TimeSpan'
          END
        WHEN 'timestamp' THEN 'Byte[]'
        WHEN 'tinyint' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Byte?'
            ELSE 'Byte'
          END
        WHEN 'uniqueidentifier' THEN CASE C.IS_NULLABLE
            WHEN 'YES' THEN 'Guid?'
            ELSE 'Guid'
          END
        WHEN 'varbinary' THEN 'Byte[]'
        WHEN 'varchar' THEN 'string'
        ELSE 'Object'
      END AS ColumnType,
      c.ORDINAL_POSITION
    FROM INFORMATION_SCHEMA.COLUMNS c
    WHERE c.TABLE_NAME = @TableName
    AND ISNULL(@TableSchema, c.TABLE_SCHEMA) = c.TABLE_SCHEMA) t
    ORDER BY t.ORDINAL_POSITION

    SET @result = @result + CHAR(13) + '#endregion Instance Properties' + CHAR(13)  

    SET @result = @result  + '}' + CHAR(13)

    IF (@TableSchema IS NOT NULL) 
    BEGIN
        SET @result = @result + CHAR(13) + '}' 
    END

    PRINT @result

它生成的c#代码如下所示:

using System;

namespace Markets
{
    public class NewsItem        {
        #region Instance Properties

        public Int32 NewsItemID { get; set; }

        public Int32? TextID { get; set; }

        public String Description { get; set; }

        #endregion Instance Properties
    }

}

It may be an idea to use EF, Linq to Sql, or even Scaffolding; however, there are times when a piece of coding like this comes in handy. Frankly, I do not like using EF navigation properties where the code it generates made 19,200 separate database calls to populate a 1000 row grid. This could have been achieved in a single database call. Nonetheless, it could just be that your technical architect does not want you to use EF and the like. So, you have to revert to code like this... Incidentally, it may also be an idea to decorate each of the properties with attributes for DataAnnotations, etc., but I'm keeping this strictly POCO.

编辑 修正了时间戳和Guid?

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....

我将几个基于SQL的答案(主要是Alex Aza的根答案)打包到kassify中,这是一个控制台应用程序,可以一次性为指定的数据库生成所有类:


例如,给定一个Users表,它是这样的:

+----+------------------+-----------+---------------------+
| Id |       Name       | Username  |        Email        |
+----+------------------+-----------+---------------------+
|  1 | Leanne Graham    | Bret      | Sincere@april.biz   |
|  2 | Ervin Howell     | Antonette | Shanna@melissa.tv   |
|  3 | Clementine Bauch | Samantha  | Nathan@yesenia.net  |
+----+------------------+-----------+---------------------+

klassify将生成一个名为Users.cs的文件,看起来像这样:

    public class User 
    {
        public int Id {get; set; }
        public string Name { get;set; }
        public string Username { get; set; }
        public string Email { get; set; }
    }

它将为每个表输出一个文件。丢弃你不用的东西。

使用

 --out, -o:
        output directory     << defaults to the current directory >>
 --user, -u:
        sql server user id   << required >>
 --password, -p:
        sql server password  << required >>
 --server, -s:
        sql server           << defaults to localhost >>
 --database, -d:
        sql database         << required >>
 --timeout, -t:
        connection timeout   << defaults to 30 >>
 --help, -h:
        show help

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'