将.net代码转换为php，在分割时发出问题

In want to read a text based rpt file and show its data column by column. I have a .net code as below which works fine:

if (long.TryParse(str1.Substring(0, 7), out result))
{
 str1.Split('|');
 string str2 = str1.Substring(194, 16);
}

I tried to write the same code in php as below:

if((int)substr($str1,0,7))
{
 $str1=split('\|', $str1);
 echo $str2 = substr($str1,194, 16);
}
else
{
 echo "<br>";
}

It says:

split(): REG_EMPTY

Please suggest an update in the code that can make the above php code work same like .net code.