The function is used to read the total number of records on the device and return the number of records for the specified data.
[in]: The handle that is returned when the connection is successful.
[in]: Data table name. Attached table 4 lists the available data tables.
[in]: The default value is null; it is used for extension.
[in]: The default value is null; it is used for extension.
When the returned value is 0 or a positive value, it indicates that the operation is successful
(the returned value indicates the number of records). When the returned value is a negative value,
it indicates that the operation fails. Attached table 5 lists the information about the error codes.
GetDeviceData
[DllImport("plcommpro.dll", EntryPoint = "GetDeviceDataCount")]
public static extern int GetDeviceDataCount(IntPtr h, string tablename, string filter, string options);
public void GetDeviceDataCount_Pull()
{
Connect_Pull();
int ret = 0;
string devtablename = "user";
string[] count = new string[20];
if (IntPtr.Zero != h)
{
MessageBox.Show("devtablename=" + devtablename + ",devdatfilter=" + "" + ",options=" + "");
ret = GetDeviceDataCount(h, devtablename, "", "");
if (ret >= 0)
MessageBox.Show("ret=" + ret);
}
else
{
MessageBox.Show("Connect device failed!");
return;
}
Disconnect_pull();
}
<DllImport("plcommpro.dll", EntryPoint:="GetDeviceDataCount")>
Public Shared Function GetDeviceDataCount(h As IntPtr, tablename As String, filter As String, options As String) As Integer
End Function
Public Sub GetDeviceDataCount_Pull()
Connect_Pull()
Dim ret As Integer = 0
Dim devtablename As String = "user"
Dim count As String() = New String(19) {}
If IntPtr.Zero <> h Then
MessageBox.Show((Convert.ToString("devtablename=") & devtablename) + ",devdatfilter=" + "" + ",options=" + "")
ret = GetDeviceDataCount(h, devtablename, "", "")
If ret >= 0 Then
MessageBox.Show("ret=" + ret)
End If
Else
MessageBox.Show("Connect device failed!")
Return
End If
Disconnect_pull()
End Sub