addsitecolumnstocontenttypes.ps1

#Credentials to connect to office 365 site collection url 
$url ="https://velegandla.sharepoint.com/sites/training"
$username="[email protected]"
$password="yourpassword"
$Password = $password |ConvertTo-SecureString -AsPlainText -force

# site column and content tye id
$Name ="SPJName"
$contentTypeId ="0x0100AEF836037845AD47AD8F87A8C5736D4E"

Write-Host "Load CSOM libraries" -foregroundcolor black -backgroundcolor yellow
Set-Location $PSScriptRoot
Add-Type -Path (Resolve-Path "Microsoft.SharePoint.Client.dll")
Add-Type -Path (Resolve-Path "Microsoft.SharePoint.Client.Runtime.dll")
Write-Host "CSOM libraries loaded successfully" -foregroundcolor black -backgroundcolor Green 

Write-Host "authenticate to SharePoint Online site collection $url and get ClientContext object" -foregroundcolor black -backgroundcolor yellow  
$Context = New-Object Microsoft.SharePoint.Client.ClientContext($url) 
$credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($username, $password) 
$Context.Credentials = $credentials 
$web = $context.Web
$fields = $web.Fields;         
$site = $context.Site 
$context.Load($web)
$context.Load($fields)
$context.Load($site)
try
{
  $context.ExecuteQuery()
  Write-Host "authenticateed to SharePoint Online site collection $url and get ClientContext object succeefully" -foregroundcolor black -backgroundcolor Green
}
catch
{
  Write-Host "Not able to authenticateed to SharePoint Online site collection $url $_.Exception.Message" -foregroundcolor black -backgroundcolor Red
  return
}


Write-Host "Check if the site column" $Name "is exist or not" -foregroundcolor black -backgroundcolor yellow  
try
{
 $field = $fields.GetByInternalNameOrTitle($Name)
 Write-Host "Site column" $Name "exist" -foregroundcolor black -backgroundcolor Green 
}
catch
{
  Write-Host "Site column" $Name "is not exist in the list of site collection columns" -foregroundcolor black -backgroundcolor Red 
  return
}

try
{
  $contentType = $web.ContentTypes.GetById($contentTypeId)
}
catch
{
  Write-Host "Content Type" $contentTypeId "not found in site content types collection."  -foregroundcolor red
  return
}

#Get all the columns associated with content type
$fieldRefCollection = $contentType.FieldLinks;
$context.Load($fieldRefCollection);
$context.ExecuteQuery();

#Add a new clumn to the content type
Write-Host "Adding site column" $Name "to the content type" -foregroundcolor black -backgroundcolor yellow 
$fieldReferenceLink = New-Object Microsoft.SharePoint.Client.FieldLinkCreationInformation
$fieldReferenceLink.Field = $field;
$contentType.FieldLinks.Add($fieldReferenceLink);
$contentType.Update($true);
try
{
  $context.ExecuteQuery();
  Write-Host "Site column" $Name "added to the content type successfully" -foregroundcolor black -backgroundcolor green
}
catch
{
  Write-Host "Error while adding site column" $Name "to the content type successfully" $_.Exception.Message -foregroundcolor black -backgroundcolor green
  return
}