以下示例创建一个 SqlConnection、一个 SqlCommand 和一个 SqlDataReader。该示例读取全部数据,并将其写到控制台。最后,该示例先关闭 SqlDataReader,再关闭 SqlConnection。[Visual Basic]
Public Sub ReadMyData(myConnString As String)
Dim mySelectQuery As String = "SELECT OrderID, CustomerID FROM Orders"
Dim myConnection As New SqlConnection(myConnString)
Dim myCommand As New SqlCommand(mySelectQuery, myConnection)
myConnection.Open()
Dim myReader As SqlDataReader
myReader = myCommand.ExecuteReader()
' Always call Read before accessing data.
While myReader.Read()
Console.WriteLine((myReader.GetInt32(0) & ", " & myReader.GetString(1)))
End While
' always call Close when done reading.
myReader.Close()
' Close the connection when done with it.
myConnection.Close()
End Sub 'ReadMyData
[C#]
public void ReadMyData(string myConnString) {
string mySelectQuery = "SELECT OrderID, CustomerID FROM Orders";
SqlConnection myConnection = new SqlConnection(myConnString);
SqlCommand myCommand = new SqlCommand(mySelectQuery,myConnection);
myConnection.Open();
SqlDataReader myReader;
myReader = myCommand.ExecuteReader();
// Always call Read before accessing data.
while (myReader.Read()) {
Console.WriteLine(myReader.GetInt32(0) + ", " + myReader.GetString(1));
}
// always call Close when done reading.
myReader.Close();
// Close the connection when done with it.
myConnection.Close();
}
[C++, JScript] 没有可用于 C++ 或 JScript 的示例。若要查看 Visual Basic 或 C# 示例,请单击页左上角的语言筛选器按钮 。
Public Sub ReadMyData(myConnString As String)
Dim mySelectQuery As String = "SELECT OrderID, CustomerID FROM Orders"
Dim myConnection As New SqlConnection(myConnString)
Dim myCommand As New SqlCommand(mySelectQuery, myConnection)
myConnection.Open()
Dim myReader As SqlDataReader
myReader = myCommand.ExecuteReader()
' Always call Read before accessing data.
While myReader.Read()
Console.WriteLine((myReader.GetInt32(0) & ", " & myReader.GetString(1)))
End While
' always call Close when done reading.
myReader.Close()
' Close the connection when done with it.
myConnection.Close()
End Sub 'ReadMyData
[C#]
public void ReadMyData(string myConnString) {
string mySelectQuery = "SELECT OrderID, CustomerID FROM Orders";
SqlConnection myConnection = new SqlConnection(myConnString);
SqlCommand myCommand = new SqlCommand(mySelectQuery,myConnection);
myConnection.Open();
SqlDataReader myReader;
myReader = myCommand.ExecuteReader();
// Always call Read before accessing data.
while (myReader.Read()) {
Console.WriteLine(myReader.GetInt32(0) + ", " + myReader.GetString(1));
}
// always call Close when done reading.
myReader.Close();
// Close the connection when done with it.
myConnection.Close();
}
[C++, JScript] 没有可用于 C++ 或 JScript 的示例。若要查看 Visual Basic 或 C# 示例,请单击页左上角的语言筛选器按钮 。
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