Template parameters

You can replace values in your template when the template is instantiated. To set up this functionality, use template parameters. Template parameters can be used to replace values such as class names and namespaces in the template. The template wizard that runs in the background when a user adds a new item or project replaces these parameters.

Declare and enable template parameters

Template parameters are declared in the format $parameter$. For example:

  • $rootnamespace$

  • $guid1$

  • $guid5$

Enable parameter substitution in templates

  1. In the .vstemplate file of the template, locate the ProjectItem element that corresponds to the item for which you want to enable parameter replacement.

  2. Set the ReplaceParameters attribute of the ProjectItem element to true.

  3. In the code file for the project item, include parameters where appropriate. For example, the following parameter specifies that the root namespace is used for the namespace in a file:

    namespace $rootnamespace$

Reserved template parameters

The following table lists the reserved template parameters that can be used by any template:

Parameter Description
clrversion Current version of the common language runtime (CLR).
ext_* Add the ext_ prefix to any parameter to refer to the variables of the parent template. For example, ext_safeprojectname.
guid[1-10] A GUID used to replace the project GUID in a project file. You can specify up to 10 unique GUIDs (for example, guid1).
itemname The name of the file in which the parameter is being used.
machinename The current computer name (for example, Computer01).
projectname The name provided by the user when the project was created. This parameter applies only to project templates.
registeredorganization The registry key value from HKLM\Software\Microsoft\Windows NT\CurrentVersion\RegisteredOrganization.
rootnamespace The root namespace of the current project followed by the subfolder of the current item, with slashes replaced by periods.
defaultnamespace The root namespace of the current project.
safeitemname Same as itemname but with all unsafe characters and spaces replaced by underscore characters.
safeitemrootname Same as safeitemname.
safeprojectname The name provided by the user when the project was created but with all unsafe characters and spaces removed. This parameter applies only to project templates.
targetframeworkversion Current version of the target .NET Framework.
time The current time in a format that's based on Windows user settings. One example of a time format is DD/MM/YYYY 00:00:00.
specifiedsolutionname The name of the solution. When "create solution directory" is checked, specifiedsolutionname has the solution name. When "create solution directory" is not checked, specifiedsolutionname is blank.
userdomain The current user domain.
username The current user name.
webnamespace The name of the current website. This parameter is used in the web form template to guarantee unique class names. If the website is at the root directory of the web server, this template parameter resolves to the root directory of the web server.
year The current year in the format YYYY.


Template parameters are case-sensitive.

Custom template parameters

You can specify your own template parameters and values, in addition to the default reserved template parameters that are used during parameter replacement. For more information, see CustomParameters element (Visual Studio templates).

Example: Use the project name for a file name

You can specify variable file names for project items by using a parameter in the TargetFileName attribute.

The following example specifies that an executable file's name uses the project name, specified by $projectname$.


Example: Use the safe project name for the namespace name

To use the safe project name for the namespace in a C# class file, use the following syntax:

namespace $safeprojectname$
    public class Class1
        public Class1()
        { }

In the .vstemplate file for the project template, include the ReplaceParameters="true" attribute when you reference the file:

    <ProjectItem ReplaceParameters="true">

See also