朋友！ 开始使用Powershell并遇到问题。 我需要在循环中以JSON格式字符串输出某些变量的值。 为此，我使用以下代码：

.....
    foreach ($value in $memoryLast5min)
    {
        $valueInt = [convert]::ToInt32($value,10);   
        if ($valueInt -ge $500MB)
        {
            $index = [array]::IndexOf($memoryLast5min,$value);        
            $JSON += @{'problemUsers' = @(
                   @{
                        "username"       = $usernames[$index]
                        "memoryLast5min" = $value
                        "readLast5min"   = $readLast5min[$index]
                        "writeLast5min"  = $writeLast5min[$index]
                    } 
                ) 
            } | ConvertTo-JSON;
        }
    }
.....
return $JSON

在变量$ JSON中，我得到以下结果：

{
    "problemUsers":  [
                         {
                             "username":  "User1","writeLast5min":  29,"memoryLast5min":  181,"readLast5min":  25
                         }
                     ]
}{
    "problemUsers":  [
                         {
                             "username":  "User2","writeLast5min":  80,"memoryLast5min":  396,"readLast5min":  74
                         }
                     ]
}{
    "problemUsers":  [
                         {
                             "username":  "User3","writeLast5min":  32,"memoryLast5min":  169,"readLast5min":  29
                         }
                     ]
}

但是我需要这个结果：

{
    "problemUsers":  [
                         {
                             "username":  "User1","readLast5min":  25
                         },{
                             "username":  "User2","readLast5min":  74
                         },{
                             "username":  "User3","readLast5min":  29
                         }
                     ]
}

请帮我修复代码