C#怎么使用ADO.Net连接数据库与实现多数据库访问
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一、ADO.Net数据库连接字符串
1、OdbcConnection（System.Data.Odbc）
(1)SQL Sever
标准安全:" Driver={SQL Server}; Server=Aron1; Database=pubs; Uid=sa; Pwd=asdasd; "
信任的连接:" Driver={SQL Server}; Server=Aron1; Database=pubs; Trusted_Connection=yes; "
(2)SQL Native Client ODBC Driver（>=SQL Server 2005）
标准安全" Driver={SQL Native Client}; Server=Aron1; Database=pubs; UID=sa; PWD=asdasd; "
信任的连接" Driver={SQL Native Client}; Server=Aron1; Database=pubs; Trusted_Connection=yes; " --Integrated Security=SSPI 等同于Trusted_Connection=yes
(3)Oracle:
新版本:"Driver={Microsoft ODBC for Oracle}; Server=OracleServer.world; Uid=Username; Pwd=asdasd; "
旧版本:"Driver={Microsoft ODBC Driver for Oracle}; ConnectString=OracleServer.world; Uid=myUsername; Pwd=myPassword; "
(4)Access:
标准安全:"Driver={Microsoft Access Driver (*.mdb)}; Dbq=C:\mydatabase.mdb; Uid=Admin; Pwd=; "
2、OleDbConnection(System.Data.OleDb)
(1)SQL Sever
标准安全:" Provider=sqloledb; Data Source=Aron1; Initial Catalog=pubs; User Id=sa; Password=asdasd; "
信任的连接:" Provider=sqloledb; Data Source=Aron1; Initial Catalog=pubs; Integrated Security=SSPI; "
(use serverName\instanceName as Data Source to use an specifik SQLServer instance, only SQLServer2000)
(2)SQL Native Client OLE DB Provider（>=SQL Server 2005）
标准安全：" Provider=SQLNCLI; Server=Aron1; Database=pubs; UID=sa; PWD=asdasd; "
信任的连接：" Provider=SQLNCLI; Server=Aron1; Database=pubs; Trusted_Connection=yes; " --Integrated Security=SSPI 等同于Trusted_Connection=yes
(3)Oracle:
标准安全:"Provider=msdaora; Data Source=MyOracleDB; User Id=UserName; Password=asdasd; "
This one's from Microsoft, the following are from Oracle
标准安全:"Provider=OraOLEDB.Oracle; Data Source=MyOracleDB; User Id=Username; Password=asdasd; "
信任的连接:"Provider=OraOLEDB.Oracle; Data Source=MyOracleDB; OSAuthent=1; "
(4)Access:
标准安全:
"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=\somepath\mydb.mdb; User Id=admin; Password=; "
3、SqlConnection(Syste.Data.SqlClient) SQL专用
标准安全:
" Data Source=Aron1; Initial Catalog=pubs; User Id=sa; Password=asdasd; "
- 或者 -" Server=Aron1; Database=pubs; User ID=sa; Password=asdasd; Trusted_Connection=False"
信任的连接:" Data Source=Aron1; Initial Catalog=pubs; Integrated Security=SSPI; "
- 或者 -" Server=Aron1; Database=pubs; Trusted_Connection=True; " –(use serverName\instanceName as Data Source to use an specifik SQLServer instance, 仅仅适用于SQLServer2000)
4、OracleConnection(System.Data.OracleClient\Oracle.ManagedDataAccess.Client) Oracle专用
标准安全："Data Source=MyOracleDB; Integrated Security=yes; " --This one works only with Oracle 8i release 3 or later
指定用户名和密码："Data Source=MyOracleDB; User Id=username; Password=passwd; Integrated Security=no; "--This one works only with Oracle 8i release 3 or later
指定主机："Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP) (HOST=192.168.115.33) (PORT=1521)))(CONNECT_DATA=(SERVICE_NAME= testDemo))); User Id=oracle_test; Password=oracle"
其中Oracle数据库服务器IP：192.168.115.33
ServiceName：testDemo
用户名：oracle_test
密码：oracle
二、利用DbProviderFactory创建各种ADO.Net对象
DbProviderFactory是一个工厂类，工厂类的作用提供其他一系列相互之间有关系的类。在这里，DbProviderFactory就自动生成了包括DbConnection、DbCommand、 DbDataAdapter等一系列数据库操作的相关类。
1、配置文件ConnectionString节：
2、利用DbProviderFactory类自动查找数据库的驱动
ConnectionStringSettings settings = ConfigurationManager.ConnectionStrings["default"];DbProviderFactory provider = DbProviderFactories.GetFactory(settings.ProviderName);
3、利用DbProviderFactory类实例创建各种ADO.Net对象。
using (DbConnection conn = provider.CreateConnection()){ conn.ConnectionString = settings.ConnectionString; conn.Open(); DbCommand cmd = conn.CreateCommand(); cmd.CommandText = "Select top 10 * From ShortTermBill"; //使用DbDataAdapter DbDataAdapter da = provider.CreateDataAdapter(); da.SelectCommand = cmd; DataSet ds = new DataSet(); da.Fill(ds); da.Dispose(); Console.WriteLine(ds.Tables[0].Rows[0]["BillCode"]); //使用DbDataReader DbDataReader reader = cmd.ExecuteReader() while (reader.Read()) { Console.WriteLine(reader.GetString(0)); } conn.Close();}三、利用DbConnection获取数据库架构信息
SQL Server 架构集合 - ADO.NET | Microsoft 官方文档
class Program{ static void Main() { string connectionString = GetConnectionString(); using (SqlConnection connection = new SqlConnection(connectionString)) { // Connect to the database then retrieve the schema information. connection.Open();string[] columnRestrictions = new String[4]; // For the array, 0-member represents Catalog; 1-member represents Schema; // 2-member represents Table Name; 3-member represents Column Name. // Now we specify the Table_Name and Column_Name of the columns what we want to get schema information. columnRestrictions[2] = "Device"; DataTable departmentIDSchemaTable = connection.GetSchema("Columns", columnRestrictions); ShowColumns(departmentIDSchemaTable); } } private static string GetConnectionString() { // To avoid storing the connection string in your code, // you can retrieve it from a configuration file. return "server=10.126.64.1;Database=TPM;user=it;pwd=;ApplicationIntent=ReadOnly;MultiSubnetFailover=True"; } private static void ShowColumns(DataTable columnsTable) { var selectedRows = from info in columnsTable.AsEnumerable() select new { TableCatalog = info["TABLE_CATALOG"], TableSchema = info["TABLE_SCHEMA"], TableName = info["TABLE_NAME"], ColumnName = info["COLUMN_NAME"], DataType = info["DATA_TYPE"], ORDINAL_POSITION = info["ORDINAL_POSITION"], COLUMN_DEFAULT = info["COLUMN_DEFAULT"], IS_NULLABLE = info["IS_NULLABLE"], CHARACTER_MAXIMUM_LENGTH = info["CHARACTER_MAXIMUM_LENGTH"], NUMERIC_PRECISION = info["NUMERIC_PRECISION"], NUMERIC_SCALE = info["NUMERIC_SCALE"], DATETIME_PRECISION = info["DATETIME_PRECISION"], }; Console.WriteLine("{0,-15},{1,-15},{2,-15},{3,-15},{4,-15},{5,-15},{6,-15},{7,-15},{8,-15},{9,-15},{10,-15},{11,-15}", "TableCatalog", "TABLE_SCHEMA", "表名", "列名", "数据类型", "字段原始顺序", "列默认值", "是否可空", "字符串最大长度", "数字精度", "数字小数点位数", "日期精度" ); foreach (var row in selectedRows) { Console.WriteLine("{0,-15},{1,-15},{2,-15},{3,-15},{4,-15},{5,-15},{6,-15},{7,-15},{8,-15},{9,-15},{10,-15},{11,-15}", row.TableCatalog, row.TableSchema, row.TableName, row.ColumnName, row.DataType, row.ORDINAL_POSITION, row.COLUMN_DEFAULT, row.IS_NULLABLE , row.CHARACTER_MAXIMUM_LENGTH, row.NUMERIC_PRECISION, row.NUMERIC_SCALE, row.DATETIME_PRECISION); } }}读到这里，这篇"C#怎么使用ADO.Net连接数据库与实现多数据库访问"文章已经介绍完毕，想要掌握这篇文章的知识点还需要大家自己动手实践使用过才能领会，如果想了解更多相关内容的文章，欢迎关注行业资讯频道。
