Use this dialog box to assign an image to a form or control in your Windows Forms application. Open the Properties window for the form or control to which the image will be assigned, select the BackgroundImage property, and then click the Ellipsis () button to open the dialog box.
Visual Studio supports two resource scopes: local and project. Select the context for your resources by clicking the appropriate radio button.
Specifies a resource in a form or control's local resource (.resx) file.
Activates the Open dialog box, which enables you to browse for an image file to import. Importing an image will cause it to be copied to your form or control's .resx file.
Removes the assigned image from your form or control's .resx file and clears the BackgroundImage property. Resetting the BackgroundImage property in the Properties window has the same effect.
Project resource file
The drop-down control lists the .resx files currently attached to your project. The images in the selected resource file appear in the lower list. Select (none) to clear the BackgroundImage property.
Shows the selected image. If the image is larger than the Preview window, the central part of the image is displayed. You can resize the dialog box to view more of the imported image.
Activates the Open dialog box, which enables you to browse for an image file to import. Importing an image will cause it to be copied to your project's Resources folder, and a reference to the copied file will be inserted into the .resx file selected in the Resource list.
To remove a background image from a form, you can also return to the Properties window, right-click the BackgroundImage property, and click Reset.