There are 2 ways that we use to pass user information to Landing Pages:
Option 1: QueryParameter
In Email:
%%[VAR @email,@name,@landingpage
Set @email = 'email@example.com'
Set @name = 'Test'
Set @landingpage = Concat('https://pub.exacttarget.com/landingpage?email=',@email,'&name=',@name)
]%%
<a href = "%%=RedirectTo(@landingpage)=%%">Click Here</a>
On LandingPage:
<form>
Name:<br>
<input type="text" name="name" value="%%=v(QueryParameter('name'))=%%"><br>
Email:<br>
<input type="text" name="email" value="%%=v(QueryParameter('email'))=%%">
</form>
Option 2: LookupRows & DataView
In Email:
%%[VAR @subscriberkey,@landingpage
Set @subscriberkey= '123456789'
Set @landingpage = Concat('https://pub.exacttarget.com/landingpage?key=',@subscriberkey)
]%%
<a href = "%%=RedirectTo(@landingpage)=%%">Click Here</a>
On LandingPage:
%%[
var @key, @email, @name
set @key = QueryParameter("key")
set @email = FIELD(ROW(LookupRows("_Subscribers","SubscriberKey",@key),1), "EmailAddress")
set @name = FIELD(ROW(LookupRows("Example_Customer_Data_DE","SubscriberKey",@key),1), "Name")
]%%
<form>
Name:<br>
<input type="text" name="name" value="%%=v(@name)=%%"><br>
Email:<br>
<input type="text" name="email" value="%%=v(@email)=%%">
</form>
Note that both of these methods are taking values from AMPScript at the time of send, and appending them to the destination URL string. For this reason, you may need some security/hashing/encoding to prevent malicious attempts to access your customer data via the form.
I hope that helps.
Best Answer
The easiest solution would be to have the URL directing your user to the CloudPage to use CloudPagesURL function. This will allow you to pass all the sendable data from your sending DE.
e.g. (in email)
<a href="%%=RedirectTo(CloudPagesURL(77))=%%" >yourPage</a>e.g. (on page)
<input type="text" Name="FirstName" value="%%=AttributeValue("FirstName")=%%">The other option is to use Lookups or LookupRows functions on the CloudPage prior to your form. To do this you will need to pass a subscriberkey or similar unique key to match inside the DE. I would recommend passing this via the CloudPagesURL as shown above. Otherwise you will need to append this to the target url in the link, which will expose it for all to see.
e.g.