<fileAssociation> Element (ClickOnce Application)
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Identifies a file extension to be associated with the application.
<fileAssociation
xmlns="urn:schemas-microsoft-com:clickonce.v1"
extension
description
progid
defaultIcon
/>
The fileAssociation element is optional. The element has the following attributes.
| Attribute | Description |
|---|---|
extension | Required. The file extension to be associated with the application. |
description | Required. A description of the file type for use by the shell. |
progid | Required. A name uniquely identifying the file type. |
defaultIcon | Required. Specifies the icon to use for files with this extension. The icon file must be specified by using the <file> Element within the <assembly> Element that contains this element. |
This element must include an XML namespace reference to "urn:schemas-microsoft-com:clickonce.v1". If the <fileAssociation> element is used, it must come after the <application> element in its parent <assembly> Element.
ClickOnce will not overwrite existing file associations. However, a ClickOnce application can override the file extension for the current user only. After that ClickOnce application is uninstalled, ClickOnce deletes the file association for the user, and the per-machine association is active again.
The following code example illustrates fileAssociation elements in an application manifest for a text editor application deployed using ClickOnce. This code example also includes the <file> Element required by the defaultIcon attribute.
<file name="text.ico" size="4286">
<hash>
<dsig:Transforms>
<dsig:Transform Algorithm="urn:schemas-microsoft-com:HashTransforms.Identity" />
</dsig:Transforms>
<dsig:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
<dsig:DigestValue>0joAqhmfeBb93ZneZv/oTMP2brY=</dsig:DigestValue>
</hash>
</file>
<file name="writing.ico" size="9662">
<hash>
<dsig:Transforms>
<dsig:Transform Algorithm="urn:schemas-microsoft-com:HashTransforms.Identity" />
</dsig:Transforms>
<dsig:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
<dsig:DigestValue>2cL2U7cm13nG40v9MQdxYKazIwI=</dsig:DigestValue>
</hash>
</file>
<fileAssociation xmlns="urn:schemas-microsoft-com:clickonce.v1" extension=".text" description="Text Document (ClickOnce)" progid="Text.Document" defaultIcon="text.ico" />
<fileAssociation xmlns="urn:schemas-microsoft-com:clickonce.v1" extension=".writing" description="Writings (ClickOnce)" progid="Writing.Document" defaultIcon="writing.ico" />