How to add a script onLoad?

I have to add a Javascript onLoad on a tag : I have a form and I want to disable an input at load.

How can I do this with symfony please ? I have to do t开发者_JAVA百科his only for forms, so I can't add it in the tag of the layout

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You can use the view.yml to add your js script only on the views containing forms. Like this:

yourViewSuccess:
  javascripts: [yourscript.js]

If you want to use the onload or onready, see this link : http://docs.jquery.com/How_jQuery_Works#Launching_Code_on_Document_Ready