ZennoLab Assemblies Documentation
IsNull Property (Document)
Example 
ZennoLab.CommandCenter Namespace > Document Class : IsNull Property
Gets a value that indicates whether or not the value of the document is null value.
Syntax
public bool IsNull {get;}

Property Value

Type: System.Boolean
true if the document value is null, otherwise false.
Example
The following code example uses the IsNull property.
public static int Execute(Instance instance, IZennoPosterProjectModel project)
{
    // clear cookies
    instance.ClearCookie();
    
    // go to lessons.zennolab.com
    Tab tab = instance.MainTab;
    if ((tab.IsVoid) || (tab.IsNull)) return -1;
    if (tab.IsBusy) tab.WaitDownloading();
    tab.Navigate("lessons.zennolab.com");
    if (tab.IsBusy) tab.WaitDownloading();
    
    // get document
    Document doc = tab.MainDocument;
    
    // if document is null then exit
    if (doc.IsNull) return -1;
    
    return 0;
}
public static function Execute($instance, $project)
{
    // clear cookies
    $instance->ClearCookie();
    
    // go to lessons.zennolab.com
    $tab = $instance->MainTab;
    if (($tab->IsVoid) || ($tab->IsNull)) return -1;
    if ($tab->IsBusy) $tab->WaitDownloading();
    $tab->Navigate("lessons.zennolab.com");
    if ($tab->IsBusy) $tab->WaitDownloading();
    
    // get document
    $doc = $tab->MainDocument;
    
    // if document is null then exit
    if ($doc->IsNull) return -1;
    
    return 0;
}
Requirements

Target Platforms: Desktop: Windows XP SP3 and older. Server: Windows Server 2003 and older.

See Also

Reference

Document Class
Document Members
IsVoid Property