Example 3

This example shows how to use JavaScript to control or configure the output of SNMP OPC Server, and how to use internal and user's defined functions. According to the input value, the output will show today's date, or current time.

First, new Script Item called DateTime is created:

Than add new JS variable input, and set the Item Path to the Data Item. The output is different, according to the input value:
   0 – View today's date
   1 – View current time
   2 – View both, date and time
   Other – Undefined command

And the script :

// according to input value, shows current date or time

// the input is a data item

function OnItemRead_DateTime(input)

{

var RetVal;

switch( input )

{

// if 0 show date

case 0 : RetVal = GetCurrentDate();

break;

// if 1 show time

case 1 : RetVal = GetCurrentTime();

break;

// if 2 show both, date and time

case 2 : RetVal = GetCurrentDate();

RetVal += " ";

RetVal += GetCurrentTime();

break;

// if 3 undefined commands

default : RetVal = "UNDEFINED COMMAND";

break;

};

return RetVal;

}

// get current date in format : "DD.MM.YYYY"

function GetCurrentDate()

{

var s = "";

dt = new Date();

s = dt.getDate(); // days

s += "." + ( dt.getMonth() + 1 ); // months

s += "." + dt.getFullYear(); // years

return s;

}

// get current time in format "HH:MM:SS"

function GetCurrentTime()

{

var s ="";

dt = new Date();

s = dt.getHours(); // hours

s += ":" + dt.getMinutes(); // minutes

s += ":" + dt.getSeconds(); // seconds

return s;

}