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寻找从数据库获取单个值的最简单方法。当你考虑使用.NET语言编写的所有9,000种方法时,这会让你感到困惑。 SqlCommands,DataReaders,Recordsets ...哦,我的!从SQL Server数据库获取数据
假设我已经连接到打开的DB。我只是希望做这样的事情:
Dim age As Integer = <SQL statement here>
寻找从数据库获取单个值的最简单方法。当你考虑使用.NET语言编写的所有9,000种方法时,这会让你感到困惑。 SqlCommands,DataReaders,Recordsets ...哦,我的!从SQL Server数据库获取数据
假设我已经连接到打开的DB。我只是希望做这样的事情:
Dim age As Integer = <SQL statement here>
SqlConnection conn = new SqlConnection("connection string goes here");
SqlCommand cmd = new SqlCommand("SELECT foo FROM ...", conn);
conn.Open();
int age = (int)cmd.ExecuteScalar();
conn.Close();
不是VB.Net的人,但我认为这将是这个样子在VB.Net:
Dim conn As SqlConnection = new SqlConnection("connection string goes here")
Dim cmd As SqlCommand = new SqlCommand("SELECT foo FROM ...", conn);
conn.Open()
Dim age As Integer = Convert.ToInt32(cmd.ExecuteScalar())
conn.Close()
试着这么做这个:
Dim age As Integer=0
Using conn As New SqlClient.SqlConnection("YourConnectionString")
Using cmd As SqlClient.SqlCommand = conn.CreateCommand()
cmd.CommandText = "SELECT Age FROM Customer WHERE CustomerNumber = @CustNum"
cmd.Parameters.AddWithValue("@CustNum", SomeCustomerNumber)
conn.Open()
age = Convert.ToInt32(cmd.ExecuteScalar().ToString())
End Using
End Using
哈哈! C#人很难使用分号! :d –