Is it at all possible to pass a parameter through a URL to an input field on a Visualforce page?

Hi Danna

you can input your parameter via URL like ap2.salesforce.com/vfPages?id=01Z90000000EkUk for example

and you can add this Id testId = ApexPages.CurrentPage().getparameters().get('id') to get the parameter from url then you can put the testId to hidden input field that you want

Hi,

Just take out the value from URL and assign it to getter setter variable and use it on your visualforce page like -

String getterSetterVar {get;set;}

getterSetterVar = ApexPages.CurrentPage().getparameters().get('URLParameter');

Hope it helps.