c#访问数据库读取指定单元格数据

首先，需要连接到数据库，可以使用SqlConnection类来实现：

string connectionString = "Data Source=YourServerName;Initial Catalog=YourDatabaseName;Integrated Security=True";
SqlConnection connection = new SqlConnection(connectionString);
connection.Open();

接着，使用SqlCommand类来执行查询语句，并使用ExecuteScalar方法来返回单个值：

string query = "SELECT YourColumnName FROM YourTableName WHERE YourCondition";
SqlCommand command = new SqlCommand(query, connection);
object result = command.ExecuteScalar();

最后，关闭数据库连接：

connection.Close();

完整的代码示例如下：

string connectionString = "Data Source=YourServerName;Initial Catalog=YourDatabaseName;Integrated Security=True";
SqlConnection connection = new SqlConnection(connectionString);
connection.Open();

string query = "SELECT YourColumnName FROM YourTableName WHERE YourCondition";
SqlCommand command = new SqlCommand(query, connection);
object result = command.ExecuteScalar();

connection.Close();

其中，YourServerName、YourDatabaseName、YourColumnName和YourTableName需要替换成实际的值，YourCondition是查询条件。