昨天讲述了以下如何在VS2005中使用form的形式来调用SAP ECC6.0中的Function Module,今天将记录一下在VS2005中以web的形式来调用Function module.
以web形式对function module进行调用与form形式基本一样,唯一值得注意的地方就是:"An ActiveX control must be run in an STA apartment. Because the attribute STAThread is applied to the Main method of a WinForm class by default with a WinForms Project, the main thread of your app will run in STA mode.".也就是说有些AcrtiveX控件或者Com组件必须运行在单线程单元下（STA：Single Thread Apartment ），否则的话会抛出“Bad variant type”异常。解决方案为：新开一个线程，并将该线程的运行模式设置为STA，然后再改线程下对Com组件或者ActiveX控件进行调用。
对应到我们的事例中，如果不使用STA模式运行，我们可以连接到SAP系统，但调用Function Module的时候会抛出“Bad variant type”异常。所以要讲调用Function Module的代码在新开的线程中执行。具体步骤如下：
一，添加对Interop.SAPFunctionsOCX.dll以及Interop.SAPLogonCtrl.dll和Interop.SAPTableFactoryCtrl.dllcom组件的引用。
二，新开一个线程，并将该线程的运行模式设置为STA. 并将登录SAP系统以及调用Function module的方法运行在该线程下！代码如下：
protected void Button1_Click(object sender, EventArgs e)
{
System.Threading.Thread s = new System.Threading.Thread(new System.Threading.ThreadStart(test)); //Create a new thread and set the method test() run in this thread
s.SetApartmentState(System.Threading.ApartmentState.STA); //Set the run mode 'STA'
s.Start(); //Start the thread
s.Join(); //Wait until thread run OK.
GridView1.DataSource = dt;
GridView1.DataBind();
msg.Text = "Get Data from 'ENQUEUE_READ' OK!";
}
private void test()
{
SAPLogonCtrl.SAPLogonControlClass login = new SAPLogonCtrl.SAPLogonControlClass();
login.ApplicationServer = "";
login.Client = "";
login.Language = "EN";
login.User = username.Text;
login.Password = Psw.Text;
login.SystemNumber = 00;
SAPLogonCtrl.Connection conn = (SAPLogonCtrl.Connection)login.NewConnection();
if (conn.Logon(0, true))
{
SAPFunctionsOCX.SAPFunctionsClass func = new SAPFunctionsOCX.SAPFunctionsClass();
func.Connection = conn;
SAPFunctionsOCX.IFunction ifunc = (SAPFunctionsOCX.IFunction)func.Add("ENQUEUE_READ");
SAPFunctionsOCX.IParameter gclient = (SAPFunctionsOCX.IParameter)ifunc.get_Exports("GCLIENT");
gclient.Value = "301";
SAPFunctionsOCX.IParameter GUNAME = (SAPFunctionsOCX.IParameter)ifunc.get_Exports("GUNAME");
GUNAME.Value = "";
SAPFunctionsOCX.IParameter LOCAL = (SAPFunctionsOCX.IParameter)ifunc.get_Exports("LOCAL");
LOCAL.Value = "0";
ifunc.Call();
SAPTableFactoryCtrl.Tables tables = (SAPTableFactoryCtrl.Tables)ifunc.Tables;
SAPTableFactoryCtrl.Table ENQ = (SAPTableFactoryCtrl.Table)tables.get_Item("ENQ");
int n = ENQ.RowCount;
dt = GetTable();
for (int i = 1; i <= n; i++)
{
DataRow dr = dt.NewRow();
dr["GNAME"] = ENQ.get_Cell(i, "GNAME").ToString();
dr["GUNAME"] = ENQ.get_Cell(i, "GUNAME").ToString();
dr["GARG"] = ENQ.get_Cell(i, "GARG").ToString();
dr["GOBJ"] = ENQ.get_Cell(i, "GOBJ").ToString();
dr["GTDATE"] = ENQ.get_Cell(i, "GTDATE").ToString();
dt.Rows.Add(dr);
}
}
}
通过以上的设置就可以在Web中调用Function Module了。此方式已经试验成功。园子里面另外一位仁兄弟到了另外一种方法http://www.cnblogs.com/jirigala/archive/2008/11/26/1341345.html 但是该方法我没有试验成功，不知道是我哪设置出问题了还是怎么回事，如果有知情者请告知，谢谢！
