Hi! I'm trying to figure out what I'm doing wrong here. I'm setting up ORM on a table. I'm using the same regex to validate serverside and clientside, but when I submit and a value passes clientside validation, I get an error:

The value does not match the regular expression pattern provided.

Here's the property in question:

<cfproperty name="name"
            fieldtype="column"
            column="user_name"
            length="16"
            ormtype="string"
            update="true"
            insert="true"
            optimisticlock="true"
            validate="regex"
            validateparams="{
                  minlength=6,
                  maxlength=16,
                  pattern=[A-Za-z0-9_]
                  }">

The input going into this is this:

<cfinput name="username"
         maxlength="16"
         length="16"
         required="true" 
         message="Invalid Username"
         tooltip="Your username must be between six and sixteen characters and can include only letters, numbers, and underscores."
         validate="regex"
         validateat="onSubmit"
         type="text"
         pattern="[A-Za-z0-9_]">

And then sticking them together:

<cfscript>
        user = EntityNew("User");
        user.setname("formdata.username");
        EntitySave(user); 
        ormflush();
</cfscript>

Since I'm using the same regex both places, I'm not sure why an error is being thrown? The client-side validation seems to be working perfectly, so did I mess something up setting up the property?

Thanks for taking a moment to read this far. I'm stumped.