Last Updated: 16 Feb 2021 13:17 by ADMIN
Created on: 10 Feb 2021 15:07
Category: Map
Type: Bug Report
RadMap: Error message occurs when deleting the images used in a LocalMapProvider

Run the attached project and follow the steps in the gif file. As a result the following exception occurs:

System.IO.IOException: 'The process cannot access the file 't_0_0_1.png' because it is being used by another process.'

1 comment
Posted on: 16 Feb 2021 05:25


This is not an issue in the controls. We are loading the tile images with the Microsoft Image.FromFile method. Loading images from the file system may lock the files on some Windows systems.  The same error can be reproduced in a similar scenario in an empty form without the RadMap control.

The scenario in the project requires to delete the images from the file system as soon as the  form with the map closes. A custom map provider loading the images as Bitmaps can help:

public class CustomLocalMapProvider : LocalMapProvider
    public override Image LoadTile(int x, int y, int zoom)
        string key = Path.Combine(this.DirectoryPath, string.Format(this.FileFormat, x, y, zoom));
        Image tile;

        if (File.Exists(key))
            using (var bmpTemp = new Bitmap(key))
                tile = new Bitmap(bmpTemp);
            tile = this.NoImageAvailable;

        return tile;

It is also necessary to call the map`s Dispose method when closing the form.

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