public bool SyncRead(object[] values, int[] itemHandle) //同步读，读的结果存放在values中，读成功返回true，失败返回false
{
IntPtr pItemValues = IntPtr.Zero;
IntPtr pErrors = IntPtr.Zero;
bool isRead = false;
try
{
if (values.Length != itemHandle.Length)
{
MessageBox.Show(string.Format("需要读出数据的个数与添加Item的数据说明长度不一致"), "读数据出错",
MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
IOPCSyncObj.Read(OPCDATASOURCE.OPC_DS_DEVICE, itemHandle.Length, itemHandle, out pItemValues, out pErrors);
int[] errors = new int[itemHandle.Length];
Marshal.Copy(pErrors, errors, 0, itemHandle.Length);
OPCITEMSTATE pItemState = new OPCITEMSTATE();
for (int i = 0; i < itemHandle.Length; i++)
{
if (errors[i] == 0)
{
pItemState = (OPCITEMSTATE)Marshal.PtrToStructure(pItemValues, typeof(OPCITEMSTATE));
values[i] = pItemState.vDataValue.ToString(); //pItemState中还包含质量和时间等信息，目前只使用了读取的数据值
// values[i] = String.Format("{0}", pItemState.vDataValue); //pItemState中还包含质量和时间等信息，目前只使用了读取的数据值
pItemValues = new IntPtr(pItemValues.ToInt32() + Marshal.SizeOf(typeof(OPCITEMSTATE)));
isRead = true;
}
else
{
String pstrError; //需不需要释放？
ServerObj.GetErrorString(errors[i], LOCALE_ID, out pstrError);
MessageBox.Show(string.Format("读出第{0}个数据时出错:{1}", i, pstrError), "读数据出错",
MessageBoxButtons.OK, MessageBoxIcon.Error);
isRead = false;
break;
}
}
}
catch (System.Exception error)
{
isRead = false;
MessageBox.Show(error.Message, "Result-Read Items", MessageBoxButtons.OK,
MessageBoxIcon.Error);
}
finally
{
if (pItemValues != IntPtr.Zero)
{
Marshal.FreeCoTaskMem(pItemValues);
pItemValues = IntPtr.Zero;
}
if (pErrors != IntPtr.Zero)
{
Marshal.FreeCoTaskMem(pErrors);
pErrors = IntPtr.Zero;
}
}
return(isRead);
}
//同步读数据
private void Btn_Read_Click(object sender, EventArgs e)
{
IntPtr pItemValues = IntPtr.Zero;
IntPtr pErrors = IntPtr.Zero;
try
{
IOPCSyncIO20Obj.Read(OPCDATASOURCE.OPC_DS_DEVICE, 2, ItemServerHandle, out pItemValues, out pErrors);
int[] errors = new int[2];
Marshal.Copy(pErrors, errors, 0, 2);
OPCITEMSTATE[] pItemState = new OPCITEMSTATE[2];
if (errors[0] == 0)
{
pItemState[0] = (OPCITEMSTATE)Marshal.PtrToStructure(pItemValues, typeof(OPCITEMSTATE));
pItemValues = new IntPtr(pItemValues.ToInt32() + Marshal.SizeOf(typeof(OPCITEMSTATE)));
Txt_R1Value.Text = String.Format("{0}", pItemState[0].vDataValue);
Txt_R1Quality.Text = GetQuality(pItemState[0].wQuality);
DateTime dt = ToDateTime(pItemState[0].ftTimeStamp);
Txt_R1TimeStamp.Text = dt.ToString();
}
if (errors[1] == 0)
{
pItemState[1] = (OPCITEMSTATE)Marshal.PtrToStructure(pItemValues, typeof(OPCITEMSTATE));
pItemValues = new IntPtr(pItemValues.ToInt32() + Marshal.SizeOf(typeof(OPCITEMSTATE)));
Txt_R2Value.Text = String.Format("{0}", pItemState[1].vDataValue);
Txt_R2Quality.Text = GetQuality(pItemState[1].wQuality);
DateTime dt = ToDateTime(pItemState[1].ftTimeStamp);
Txt_R2TimeStamp.Text = dt.ToString();
}
}
catch (System.Exception error)
{
MessageBox.Show(error.Message, "Result-Read Items", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
//free the memory
if (pItemValues != IntPtr.Zero)
{
Marshal.FreeCoTaskMem(pItemValues);
pItemValues = IntPtr.Zero;
}
if (pErrors != IntPtr.Zero)
{
Marshal.FreeCoTaskMem(pErrors);
pErrors = IntPtr.Zero;
}
}
}
