Find Control

[robertfah]

I've written an app that uses permissions stored in a DB for each control on a given form within the app. How can I go through each Control on a given form and find the coresponding control name (pulled from the DB) and make it Enabled/Disabled?

I know I have to loop through the Controls collection and do that recursively because the given control could have children controls, but I can't seem to get it to work. Here's my code:

//Set Permissions...
Permissions oPermissions = new Permissions();
DataSet dsPermissions = oPermissions.GetGroupPermissions(Forms.FormNames.frmMain, Users.Instance.GroupID);

for (int x = 0; x < dsPermissions.Tables[0].Rows.Count; x++)
    FindAllControls(dsPermissions.Tables[0].Rows[x], this);

this is the FindAllControls method...

private void FindAllControls(DataRow dr, Control ctrl)
{
    foreach (Control c in ctrl.Controls)
    {
        if (c.Name == dr["ControlName"].ToString())
            c.Enabled = Convert.ToBoolean(dr["Enabled"].ToString());
        else if (c.HasChildren)
            FindAllControls(dr, c);
    }
}

 

[RyanEK]

Remove the "else" statement in your recursive method. Otherwise it does not loop to a control which is contained within another control.

 

[robertfah]

RyanEK,

Thanks for that....I was so involved that day that I overlooked that. Thanks again.

I found some interesting things about controls and whatnot. I have a Menu Strip msMenu that has sub menu items and those sub menu items may have sub menu items as well. So, when I used the above code, it never processed the sub menu items because they are of a different type (not Control). I ended up storing the type in the DB along with the control name and whether or not it should be enabled or not. So the new code uses 2 functions that are recursive within each other, like so:

private void TraverseMenuItems(DataRow dr, ToolStripMenuItem tsmi)
{
    //Process any Children that are of the type ToolStripMenuItem (purposely skipping 
    //ToolStripSeparator types).
    if (tsmi.GetType() == typeof (ToolStripMenuItem))
    {
        //Process menu items
        for (int x = 0; x < tsmi.DropDownItems.Count; x++)
        {
            //If the tsic[x] matches the datarow (menu item) then set it's Enabled property
            //to the value that's in the DB.
            if(tsmi.DropDownItems[x].Name == dr["ControlName"].ToString())
                tsmi.DropDownItems[x].Enabled = Convert.ToBoolean(dr["Enabled"]);
            
            //Process sub-menu items.
            TraverseSubMenuItems(dr, tsmi.DropDownItems);
        }
    }
}

private void TraverseSubMenuItems(DataRow dr, ToolStripItemCollection tsic)
{
    //Loop through each item in this Menu Item DropDownItems.
    for (int x = 0; x < tsic.Count; x++)
    {
        //If the tsic[x] matches the datarow (menu item) then set it's Enabled property
        //to the value that's in the DB.
        if (tsic[x].Name == dr["ControlName"].ToString())
            tsic[x].Enabled = Convert.ToBoolean(dr["Enabled"]);
        
        //Process any Children that are of the type ToolStripMenuItem (purposely skipping 
        //ToolStripSeparator types).
        if (tsic[x].GetType() == typeof(ToolStripMenuItem))
        {
            //Convert the ToolStripItemCollection tsic to a ToolStripMenuItem
            //and call the TraverseMenuItems recursive function to check for children.
            ToolStripMenuItem tsmi = (ToolStripMenuItem)tsic[x];
            TraverseMenuItems(dr, tsmi);
        }
    }
}

I had to use the typeof because Separators are not of the type ToolStripMenuItem, so there was a casting error if that statement isn't included. So all I do now is pass in the datarow and the name of the menu control to process and it works like a charm.