PHP Function to Replace Tags with Data

I need a clean php function that inputs a source file and replaces tags with data. I am providing a php file that has a multidimensional array with the following structure: FORM1 FIELD1->TYPE FIELD2->TYPE FIELD3->TYPE FORM1 FIELD1->TYPE FIELD2->TYPE ... Then I'm providing a source file that has two special commands in it: <for_each #ELEMENT#></for_each> <name #ELEMENT#> Where #ELEMENT# will be replaced with either "form", "[login to view URL]", or "[login to view URL]". You must write a php function that imports the source file and replaces the for_each and name tags appropriately. For example look at the following source line: Here are all my forms: <for_each form><name form>, </for_each> Aren't they cool! The previous line will be converted to: Here are all my forms: Form1, Form2, Aren't they cool! Please review the attached files to see more the detailed source and php files.