1.) user inputs text in a one-line text area (html form), if it contains any other characters than letters, numbers and _ it deletes the character and gives a visible error to the user.
So in short:
username - okay
user_name_3 - okay
user* - not okay, deletes * and gives error
2.) user inputs text in a one-line text area (html form), it fills out another one-line text area (in the same form) after sending the text through a web-safe cleanup function (i have that code in php, not sure how helpful that is, you will probably need to adapt it a bit, but it's really easy)
area1: This Is Something I Wrote
3.) Randomize date - there are three dropdowns in the html form - one for year, one for month and one for day. I would need a button or something to click that would randomize these values, preferably over the next 6 months.