Not able to use parameter with dynamic placeholder

Question

I am going through Sitecore training and currently stuck on module working with component parameters

Here I am trying to change the number of spaces by passing through a parameter.

Here is my code and also an ss of how I am trying to add parameter through experience editor:

Answer 1

Could you please add MaxCount, just like below code and in this link?

@Html.Sitecore().DynamicPlaceholder(new DynamicPlaceholderDefinition("placeholderkey")
    {
        Count = 3,
        MaxCount = 9,
        Seed = 9,
        OutputModifier = (input, context) => new HtmlString("<div class=\"large-4 small-12 columns\">" + input + "</div>"),
    })

also please confirm "ph_feature_spot_count" is a correct placeholder name.

Answer 2

Above issue got resolved once I changed the additional parameter name to below as the placeholder name was "feature-spot" and not "feature_spot"

ph_feature-spot_count

The parameters must follow a specific format:

ph_placeholderKey_paramName where placeholderKey is the key in your code (customkey in last example) and paramName is the parameter name that will be passed through. Count is a special param name that defines the number of placeholders to generate.

ph_placeholderKey_indexNumber_paramName where indexNumber is the placeholder index number. This allows you to only pass specific parameters to specific placeholders, e.g. If you wanted to pass a different CSS Class to the second placeholder to make it “featured”. Keep in mind that the number is 0 based.

Ref Url: https://jammykam.wordpress.com/2017/10/17/sitecore-9-dynamic-placeholders/