FormIt and Register use the same syntax. If you can get mChimpx and FormIt working it will be an identical implementation. The instructions for mChimpX could provide an example but you would basically just need to do something similar as this to your Register Snippet call (I excluded all other optional Register properties for this example):
[[!Register?
&hooks=`mChimpX`
&mcApiKey=`(Your MC API Key)`
&mcListId=`(LIST ID)`
&mcEmailField=`email`
&mcMergeTags=`FNAME:firstname,LNAME:surname,MERGE9:yourcustomfield`
]]
You form would then look like:
<div class="register">
<div class="registerMessage">[[!+reg.error.message]]</div>
<form class="form" action="[[~[[*id]]]]" method="post">
<input type="hidden" name="nospam" value="[[!+reg.nospam]]" />
<label for="username">[[%register.username? &namespace=`login` &topic=`register`]]
<span class="error">[[!+reg.error.username]]</span>
</label>
<input type="text" name="username" id="username" value="[[!+reg.username]]" />
<label for="password">[[%register.password]]
<span class="error">[[!+reg.error.password]]</span>
</label>
<input type="password" name="password" id="password" value="[[!+reg.password]]" />
<label for="password_confirm">[[%register.password_confirm]]
<span class="error">[[!+reg.error.password_confirm]]</span>
</label>
<input type="password" name="password_confirm" id="password_confirm" value="[[!+reg.password_confirm]]" />
<label for="firstname">[[%register.firstname]]
<span class="error">[[!+reg.error.firstname]]</span>
</label>
<input type="text" name="firstname" id="firstname" value="[[!+reg.firstname]]" />
<label for="lastname">[[%register.lastname]]
<span class="error">[[!+reg.error.lasttname]]</span>
</label>
<input type="text" name="lastname" id="lastname" value="[[!+reg.lastname]]" />
<label for="email">[[%register.email]]
<span class="error">[[!+reg.error.email]]</span>
</label>
<input type="text" name="email" id="email" value="[[!+reg.email]]" />
<label for="yourcustomfield">Your Custom Field
<span class="error">[[!+reg.error.yourcustomfield]]</span>
</label>
<input type="text" name="yourcustomfield" id="yourcustomfield" value="[[!+reg.yourcustomfield]" />
<div class="form-buttons">
<input type="submit" name="registerbtn" value="Register" />
</div>
</form>
</div>
]]
The only drawback of this right now is that MODX expects a fullname for the value of the registration of the name whereas MailChimp expects the typical value of first and last names. This could be resolved by using a hook to set the value of fullname by merging the first and last values into one value.
The properties and expected values and purpose for mChimpX are listed here:
http://rtfm.modx.com/display/ADDON/mChimpX
[ed. note: smashingred last edited this post 12 years, 6 months ago.]