How to add items in SharePoint List with values from 2 different lists

Question

My program must verify this requirement :

Add Owner value from List A where Name (in list A) eq Name (in list B): Here i want to nested the first Foreach in the second one

Add-PSSnapin Microsoft.SharePoint.PowerShell
$web = get-spweb http://intranet/Operations/
$todolist = $web.Lists["ToDo"]
$checkList = $web.Lists["CheckList"]

$Fund = get-spweb http://sites/clients
$PersonsList = $Fund.Lists["Client Allocation"]

$today = Get-Date

foreach ($person in $PersonsList.Items | Where $_["Fund"] -eq "Agenda") 
{
   $checkListItem = $checkList.Items.Add()

   $checkListItem["Assigned To"]= $Person["Risk Manager In charge"]
   $checkListItem["Backup"] = $Person["Backup"]

   $checkListItem.Update()
}

foreach ($task in $todolist.Items) 
{
   $checkListItem = $checkList.Items.Add()

   $checkListItem["StartDate"] = $today.ToShortDateString()
   $checkListItem["DueDate"] = $today.ToShortDateString()
   $checkListItem["Fund Name"] = $task["Fund"].Tostring().Split("|")[0]
   $checkListItem["Task Name"] = $task["Fund"].Label + " -> " + $task["Title"]
   $checkListItem["Link"] = $task["Link"]
   $checkListItem["Details"] = $task["Details"]

   # I want To make here the result of the first Foreach where Title of the checklist eq to the Title Of fund List
   # $checkListItem["Assigned To"] = $Fund.$PersonsList["Risk Manager In charge"]

   $checkListItem.Update()
}

Answer 1

I would go for this pseudo-code - adjust as You need it (different webs, lists and fields, but idea should stay the same).

$snapin = Get-PSSnapin | Where-Object {$_.Name -eq 'Microsoft.SharePoint.Powershell'}
if ($snapin -eq $null) { Add-PSSnapin Microsoft.SharePoint.Powershell }

$web = Get-SPWeb "https://www.contoso.com"

$listSource1 = $web.Lists["List Name 1"]
$listSource2 = $web.Lists["List Name 2"]

$listTarget = $web.Lists["List Name 3"]

foreach($item1 in $listSource1.Items)
{
    $commonValue = $item1["Title"]

    $query = New-Object Microsoft.SharePoint.SPQuery
    $query.ViewAttributes = "Scope='Recursive'"
    $query.Query = "<Where><Contains><FieldRef Name='Title' /><Value Type='Text'>" + $commonValue + "</Value></Contains></Where>"
    $query.RowLimit = 10    
    # leave value 10 to catch if multiple items are found OR change to 1 and remove "if-else-else" if you are sure for unique matching

    $items2 = $listSource2.GetItems($query)

    if($items2.Count -eq 1)
    {   
        # if values are unique, item collection "$items2" should contain only one item 
        $item2 = $items2[0]

        $newItem = $listTarget.Items.Add();

        $newItem["Field 1"] = $item1["Other Field 1"]
        $newItem["Field 2"] = $item1["Other Field 2"]

        $newItem["Field 3"] = $item2["Other Field 3"]
        $newItem["Field 4"] = $item2["Other Field 4"]

        $newItem.Update()
    } 
    else if ($items2.Count -eq 0)   
    {
        Write-host "# No matching items found for value:" + $commonValue 
    } 
    else 
    {
        Write-host "# Multiple matching items found for value:" + $commonValue 
    }
}
$web.Dispose();
Write-Host "End" -b DarkGreen -f Green

Notice: this code will work efficiently if total item count in lists is below hundreds-of-thousands.

Answer 2

you can use below pseudo code

foreach ($task in $todolist.Items) 
{
    foreach ($chkItem in $checkList.Items) 
    {
        if ($task["Owner"] -eq $chkItem["Owner"]){

            your code to update/insert
            break;
        }
    }
}