Create Sharepoint Site Group and role definition through powershell

Below code to be used in powershell file


function createSiteGroups($groupName,$groupOwner,$groupDescription,$permissionLevel,$users)
{
    Write-Host  -foreground "green"  "Creating Sharepoint group -" $groupName
    $web.SiteGroups.Add($groupName, $groupOwner, $groupOwner, $groupDescription)
    $Group = $web.SiteGroups[$groupName]
    $Group.AllowMembersEditMembership = $true
    $Group.Update()
    Write-Host  -foreground "green"  "Creating role assignment for the group -" $groupName
    $GroupAssignment = new-object Microsoft.SharePoint.SPRoleAssignment($Group)

    #Get the permission levels to apply to the new groups
    $RoleDefinition = $web.Site.RootWeb.RoleDefinitions[$permissionLevel]
    #Assign the groups the appropriate permission level
    $GroupAssignment.RoleDefinitionBindings.Add($RoleDefinition)
    #Add the group to the site with the permission level
    $web.RoleAssignments.Add($GroupAssignment)
    Write-Host  -foreground "green"  "Creation of group and role assignment completed successfully for the group -" $groupName
    #Adding users to the group
    Write-Host  -foreground "green"  "Adding users to the group -" $groupName
    $arrayUsers = $users.split(",")
    foreach($user in $arrayUsers)
        {
           if($user -ne "")
             {
               $adUser = $web.Site.RootWeb.EnsureUser($user)
               $Group.AddUser($adUser)
              }
        }
}


You can call the function as below

#Creating Sharepoint security Groups
#create group "Group1 "
$groupName = "Group1"
$groupOwner = $web.Site.Owner
$groupDescription =  "test Group"
$permissionLevel = "Full Control"
$users = "domain\user1,Domain\user2"
createSiteGroups $groupName  $groupOwner $groupDescription $permissionLevel $users