Hashtable - update the value

Question

_{Wednesday, April 2, 2014 9:42 PM}

I am trying to update the Value of a hash table, if there is a True condition.  My false condition works fine.   I am unclear how to update the value in a hash table, if there is a key that is true.

thank you for your help 

File.csv
name,count
a,1
b,2
c,10
d,11

the $hash table results would be.
"a=1","b=2","c=13","d=11"

Script: 

$import = import-csv ("c:\file.csv")

$Hash=@{
"a"="1";"b"="2";"c"="3"
}

foreach ($item in $import)
{
$Importedname = $item.name
$Importedcount = $item.count

if ($hash.ContainsKey($Importedname))
{

Write-Host "True" $Importedname

}
Else
{
$hash.Add("$Importedname","$Importedcount")
Write-Host "False"
}
}

All replies (4)

_{Thursday, April 3, 2014 12:16 AM ✅Answered}

It's unusual to call the set_Item method like that.  Typically, you'll see this syntax instead:

$hash['c'] += 10

However, be careful of how you defined your hashtable.  Right now, the values are strings instead of numbers, and "3" + 10 would produce the string "310".  Instead, define the hashtable to contain integers:

 $Hash=@{
 "a" = 1
 "b" = 2
 "c" = 3
 }

 $Hash['c'] += 10

 $Hash

_{Wednesday, April 2, 2014 10:07 PM}

Try this using the Set_Item Method:

$import = import-csv ("c:\file.csv")

 $Hash=@{
 "a"="1"
 "b"="2"
 "c"="3"
 }


 foreach ($item in $import)
{
$Importedname = $item.name
$Importedcount = $item.count

if ($hash.ContainsKey($Importedname))
{

Write-Host "True" $Importedname
$Hash.set_Item($Importedname,$Importedcount)

}
Else
{
$hash.Add("$Importedname","$Importedcount")
Write-Host "False"
}
}

P.s:

If you would like to see all the methods type $Hash | Get-Member -Force

_{Wednesday, April 2, 2014 10:39 PM}

Thank you for your reply.   the only issue,  I need to add the two values.    So, $hash c=3,  and $item c=10  would need to update the $hash value c=3  to be, c=13.   is there a way to add the two values and then update it with the set_item.

_{Thursday, April 3, 2014 12:21 AM}

thank you that worked.