t4必须DbHelper.ttinclude t4连接数据库获取表必须

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<#+
//连接数据库配置
public class config
{
public static readonly string [email protected]"server=.;pwd=123;uid=sa;database=oademo;";
public static readonly string DbDatabase="oademo";
}

public class DbHelper
{

#region GetDbTables
//获取数据库所有的表
public static List<DbTable> GetDbTables(string connectionString, string database, string tables = null)
{

if (!string.IsNullOrEmpty(tables))
{
tables = string.Format(" and obj.name in (‘{0}‘)", tables.Replace(",", "‘,‘"));
}
#region SQL
string sql = string.Format(@"SELECT
obj.name tablename,
schem.name schemname,
idx.rows,
CAST
(
CASE 
WHEN (SELECT COUNT(1) FROM sys.indexes WHERE object_id= obj.OBJECT_ID AND is_primary_key=1) >=1 THEN 1
ELSE 0
END 
AS BIT) HasPrimaryKey 
from {0}.sys.objects obj 
inner join {0}.dbo.sysindexes idx on obj.object_id=idx.id and idx.indid<=1
INNER JOIN {0}.sys.schemas schem ON obj.schema_id=schem.schema_id
where type=‘U‘ {1}
order by obj.name", database, tables);
#endregion
DataTable dt = GetDataTable(connectionString, sql);
return dt.Rows.Cast<DataRow>().Select(row => new DbTable
{
TableName = row.Field<string>("tablename"),
SchemaName = row.Field<string>("schemname"),
Rows = row.Field<int>("rows"),
HasPrimaryKey = row.Field<bool>("HasPrimaryKey")
}).ToList();
}
#endregion

#region GetDbColumns
//获取某个表所有的列
public static List<DbColumn> GetDbColumns(string connectionString, string database, string tableName, string schema = "dbo")
{
#region SQL
string sql = string.Format(@"
WITH indexCTE AS
(
SELECT 
ic.column_id,
ic.index_column_id,
ic.object_id 
FROM {0}.sys.indexes idx
INNER JOIN {0}.sys.index_columns ic ON idx.index_id = ic.index_id AND idx.object_id = ic.object_id
WHERE idx.object_id =OBJECT_ID(@tableName) AND idx.is_primary_key=1
)
select
colm.column_id ColumnID,
CAST(CASE WHEN indexCTE.column_id IS NULL THEN 0 ELSE 1 END AS BIT) IsPrimaryKey,
colm.name ColumnName,
systype.name ColumnType,
colm.is_identity IsIdentity,
colm.is_nullable IsNullable,
cast(colm.max_length as int) ByteLength,
(
case 
when systype.name=‘nvarchar‘ and colm.max_length>0 then colm.max_length/2 
when systype.name=‘nchar‘ and colm.max_length>0 then colm.max_length/2
when systype.name=‘ntext‘ and colm.max_length>0 then colm.max_length/2 
else colm.max_length
end
) CharLength,
cast(colm.precision as int) Precision,
cast(colm.scale as int) Scale,
prop.value Remark
from {0}.sys.columns colm
inner join {0}.sys.types systype on colm.system_type_id=systype.system_type_id and colm.user_type_id=systype.user_type_id
left join {0}.sys.extended_properties prop on colm.object_id=prop.major_id and colm.column_id=prop.minor_id
LEFT JOIN indexCTE ON colm.column_id=indexCTE.column_id AND colm.object_id=indexCTE.object_id 
where colm.object_id=OBJECT_ID(@tableName)
order by colm.column_id", database);
#endregion
SqlParameter param = new SqlParameter("@tableName", SqlDbType.NVarChar, 100) { Value = string.Format("{0}.{1}.{2}", database, schema, tableName) };
DataTable dt = GetDataTable(connectionString, sql, param);
return dt.Rows.Cast<DataRow>().Select(row => new DbColumn()
{
ColumnID = row.Field<int>("ColumnID"),
IsPrimaryKey = row.Field<bool>("IsPrimaryKey"),
ColumnName = row.Field<string>("ColumnName"),
ColumnType = row.Field<string>("ColumnType"),
IsIdentity = row.Field<bool>("IsIdentity"),
IsNullable = row.Field<bool>("IsNullable"),
ByteLength = row.Field<int>("ByteLength"),
CharLength = row.Field<int>("CharLength"),
Scale = row.Field<int>("Scale"),
Remark = row["Remark"].ToString()
}).ToList();
}

#endregion

#region GetFiles
//获取非主键的所有列
public static string GetFileStr(string tableName){
StringBuilder fields = new StringBuilder();
foreach(DbColumn column in DbHelper.GetDbColumns(config.ConnectionString, config.DbDatabase, tableName)) {

if(!column.IsIdentity) {
fields.Append(column.ColumnName);
fields.Append(",");
}

}
fields.Remove(fields.Length-1,1);
return fields.ToString();
}
//获取 @值 类型的参数
public static string GetParStr(string tableName){
StringBuilder fields = new StringBuilder();
foreach(DbColumn column in DbHelper.GetDbColumns(config.ConnectionString, config.DbDatabase, tableName)) {

if(!column.IsIdentity) {
fields.Append("@"+column.ColumnName);
fields.Append(",");
}

}
fields.Remove(fields.Length-1,1);
return fields.ToString();
}
#endregion


#region GetDataTable
//根据一个sql查询表
public static DataTable GetDataTable(string connectionString, string commandText, params SqlParameter[] parms)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand command = connection.CreateCommand();
command.CommandText = commandText;
command.Parameters.AddRange(parms);
SqlDataAdapter adapter = new SqlDataAdapter(command);

DataTable dt = new DataTable();
adapter.Fill(dt);

return dt;
}
}

#endregion

//获取主键
public static string GetPrimaryKey (string tableName)
{
foreach(DbColumn column in DbHelper.GetDbColumns(config.ConnectionString, config.DbDatabase, tableName)) {

if(column.IsIdentity) {
return column.ColumnName;
}

}
return "";
}

}

 

#region DbTable
/// <summary>
/// 表结构
/// </summary>
public sealed class DbTable
{
/// <summary>
/// 表名称
/// </summary>
public string TableName { get; set; }
/// <summary>
/// 表的架构
/// </summary>
public string SchemaName { get; set; }
/// <summary>
/// 表的记录数
/// </summary>
public int Rows { get; set; }

/// <summary>
/// 是否含有主键
/// </summary>
public bool HasPrimaryKey { get; set; }
}
#endregion

#region DbColumn
/// <summary>
/// 表字段结构
/// </summary>
public sealed class DbColumn
{
/// <summary>
/// 字段ID
/// </summary>
public int ColumnID { get; set; }

/// <summary>
/// 是否主键
/// </summary>
public bool IsPrimaryKey { get; set; }

/// <summary>
/// 字段名称
/// </summary>
public string ColumnName { get; set; }

/// <summary>
/// 字段类型
/// </summary>
public string ColumnType { get; set; }

/// <summary>
/// 数据库类型对应的C#类型
/// </summary>
public string CSharpType
{
get
{
return SqlServerDbTypeMap.MapCsharpType(ColumnType);
}
}

/// <summary>
/// 
/// </summary>
public Type CommonType
{
get
{
return SqlServerDbTypeMap.MapCommonType(ColumnType);
}
}

/// <summary>
/// 字节长度
/// </summary>
public int ByteLength { get; set; }

/// <summary>
/// 字符长度
/// </summary>
public int CharLength { get; set; }

/// <summary>
/// 小数位
/// </summary>
public int Scale { get; set; }

/// <summary>
/// 是否自增列
/// </summary>
public bool IsIdentity { get; set; }

/// <summary>
/// 是否允许空
/// </summary>
public bool IsNullable { get; set; }

/// <summary>
/// 描述
/// </summary>
public string Remark { get; set; }
}
#endregion

#region SqlServerDbTypeMap

public class SqlServerDbTypeMap
{
public static string MapCsharpType(string dbtype)
{
if (string.IsNullOrEmpty(dbtype)) return dbtype;
dbtype = dbtype.ToLower();
string csharpType = "object";
switch (dbtype)
{
case "bigint": csharpType = "long"; break;
case "binary": csharpType = "byte[]"; break;
case "bit": csharpType = "bool"; break;
case "char": csharpType = "string"; break;
case "date": csharpType = "DateTime"; break;
case "datetime": csharpType = "DateTime"; break;
case "datetime2": csharpType = "DateTime"; break;
case "datetimeoffset": csharpType = "DateTimeOffset"; break;
case "decimal": csharpType = "decimal"; break;
case "float": csharpType = "double"; break;
case "image": csharpType = "byte[]"; break;
case "int": csharpType = "int"; break;
case "money": csharpType = "decimal"; break;
case "nchar": csharpType = "string"; break;
case "ntext": csharpType = "string"; break;
case "numeric": csharpType = "decimal"; break;
case "nvarchar": csharpType = "string"; break;
case "real": csharpType = "Single"; break;
case "smalldatetime": csharpType = "DateTime"; break;
case "smallint": csharpType = "short"; break;
case "smallmoney": csharpType = "decimal"; break;
case "sql_variant": csharpType = "object"; break;
case "sysname": csharpType = "object"; break;
case "text": csharpType = "string"; break;
case "time": csharpType = "TimeSpan"; break;
case "timestamp": csharpType = "byte[]"; break;
case "tinyint": csharpType = "byte"; break;
case "uniqueidentifier": csharpType = "Guid"; break;
case "varbinary": csharpType = "byte[]"; break;
case "varchar": csharpType = "string"; break;
case "xml": csharpType = "string"; break;
default: csharpType = "object"; break;
}
return csharpType;
}

public static Type MapCommonType(string dbtype)
{
if (string.IsNullOrEmpty(dbtype)) return Type.Missing.GetType();
dbtype = dbtype.ToLower();
Type commonType = typeof(object);
switch (dbtype)
{
case "bigint": commonType = typeof(long); break;
case "binary": commonType = typeof(byte[]); break;
case "bit": commonType = typeof(bool); break;
case "char": commonType = typeof(string); break;
case "date": commonType = typeof(DateTime); break;
case "datetime": commonType = typeof(DateTime); break;
case "datetime2": commonType = typeof(DateTime); break;
case "datetimeoffset": commonType = typeof(DateTimeOffset); break;
case "decimal": commonType = typeof(decimal); break;
case "float": commonType = typeof(double); break;
case "image": commonType = typeof(byte[]); break;
case "int": commonType = typeof(int); break;
case "money": commonType = typeof(decimal); break;
case "nchar": commonType = typeof(string); break;
case "ntext": commonType = typeof(string); break;
case "numeric": commonType = typeof(decimal); break;
case "nvarchar": commonType = typeof(string); break;
case "real": commonType = typeof(Single); break;
case "smalldatetime": commonType = typeof(DateTime); break;
case "smallint": commonType = typeof(short); break;
case "smallmoney": commonType = typeof(decimal); break;
case "sql_variant": commonType = typeof(object); break;
case "sysname": commonType = typeof(object); break;
case "text": commonType = typeof(string); break;
case "time": commonType = typeof(TimeSpan); break;
case "timestamp": commonType = typeof(byte[]); break;
case "tinyint": commonType = typeof(byte); break;
case "uniqueidentifier": commonType = typeof(Guid); break;
case "varbinary": commonType = typeof(byte[]); break;
case "varchar": commonType = typeof(string); break;
case "xml": commonType = typeof(string); break;
default: commonType = typeof(object); break;
}
return commonType;
}
}
#endregion

#>

 

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