如何将此VB.NET代码转换为C＃？

Question

Dim MaxItemID As Integer
Dim objCMD As New SqlCommand(StrSql, objConn)  
MaxItemID = IIf(IsDBNull(objCMD.ExecuteScalar()), 0, objCMD.ExecuteScalar()) + 1

如何在C＃中执行此操作？

Answer 1

int MaxItemID = 0;
using(SqlCommand objCMD = new SqlCommand(StrSql, objConn))
{
    MaxItemID = (Converter.IsDBNull(objCMD.ExecuteScalar()) ? 0 : objCMD.ExecuteScalar()) + 1;
}

Answer 2

int MaxItemID;
SqlCommand objCMD =new SqlCommand (StrSql, objConn);
MaxItemID = IsDBNull(objCMD.ExecuteScalar()? 0: objCMD.ExecuteScalar()) + 1;

Answer 3

这应该这样做（并避免执行SQL两次）：

var objCMD = new SqlCommand(StrSql, objConn);
var sqlRes = objCMD.ExecuteScalar();
int maxItemID = 1 + (Convert.IsDBNull(sqlRes) ? 0 : (int)sqlRes);

注意VB会隐式地将object ExecuteScalar的{​​{1}}返回转换为int，但C＃不会。