Enumerating through Keys

foreach ($key in $var1.Keys) {
    $value = $var1[$key]
    # or
    $value = $var1.$key 
}

Enumerating through Key-Value Pairs

foreach ($keyvaluepair in $var1.GetEnumerator()) {
    $key1 = $_.Key1
    $val1 = $_.Val1
}