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how to check if (c#) ControlCollection.Find() has returned a result

开发者 https://www.devze.com 2023-02-24 05:50 出处:网络
I am using ControlCollection.Find() method in C# to find some picture boxes present in my form. I am storing the returned result in a Control[] array. How do I find out if the Find() was successful or

I am using ControlCollection.Find() method in C# to find some picture boxes present in my form.

I am storing the returned result in a Control[] array. How do I find out if the Find() was successful or not???

Code

Control[] temp = pictureBoxCollection.Find(TagNo, true);
if(temp.Length>0)
    UpdateRes = update_status(TagNo, Status);

where TagNo is a string c开发者_StackOverflow中文版ontaining the Control's exact name.

Yes. I'm using the control's exact name. And I have used the Find() method successfully earlier (when the Control was surely present in the Collection). I am having a problem this time because the control may or may not be present in the Collection.


Have you tried?

var result = controlCollection.Find(contolName,true);
if(result == null || result.Length == 0)
{
   // fail to find
}

You can use this method to see list of all controls

    public void FillControls(List<string> container,Control control)
    {
        foreach (Control child in control.Controls)
        {
            container.Add(child.Name);
            FillControls(container,child);
        }
    }

And then use:

    public Form1()
    {
        InitializeComponent();

        List<string> controls = new List<string>();
        FillControls(controls,this);
    }


Safest way will be to check if the returned array is not null and has Length of more than 0:

Control[] children = this.Find("mypic", true);
if (children != null && children.Length > 0)
{
   //OK to proceed...
}


Find() method will return an empty array (never null) if no controls were found. So you should simply do something like:

Control[] controls = myForm.Find("picbox", true);
if (controls.Length > 0) {
   // Do logic when picture boxes are found
} else {
   // Do logic when there are no picture boxes
}
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