为wordpress自定义字段脚本集成if-else循环

I search a lot, but I don´t finde the right solution.

I have a custome field, called "My-Name". This custome field can be added at a post (more then once) or not.

$my_name = get_post_custom_values( 'My-Name' );
foreach ( $my_name as $my_name )
echo $my_name;

My problem - if this key is not available at a post, I get an Error (Warning: Invalid argument supplied for foreach()).

I dont want this Error-Message, I want an "else = html text" if the key isn´t available at this post. I try some if / else, but my php skills are too low for a sucess. Can someone help me?

UPDATE:
I have modify the script from dingo_d and now it works - thx!

$my_name = get_post_custom_values( 'My-Name' );

if(is_array($my_name) && !empty($my_name)){
    foreach($my_name as $my_name){
    echo $my_name . "
";
    }
} else{
    echo 'My text';
}

 $my_name = get_post_custom_values( 'My-Name' );

 if(isset($my_name))
  {
    foreach ( $my_name as $my_name ){
      echo $my_name;
    }
  }else{
   echo "html goes here";
  }

Depending on what get_post_custom_values() will return on a missing POST param, just check for the parameter being set or empty:

if (isset($my_name))
{
    foreach(...) ...
}

vs.

if (!empty($my_name))
{
    foreach(...) ...
}

By the way: An if-else-construct is not a loop ;-)

Always check if your variable is filled with something before entering the foreach loop. That also depends on the type of return you expect as well. I'd do something like:

if(is_array($my_name) && !empty($my_name)){
    foreach($my_name as $value){
        echo $value;
    }
} else{
    echo 'My text';
}

This is because your $my_name variable should return an array. Should your return value be string you'd check if it's set and if it's not an empty string with

if(isset($my_variable) && $my_variable != ''){...}