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Order Area TOCTitle ContentId PageTitle DateApproved MetaDescription
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editor
Creating snippets
79CD9B45-97FF-48B1-8DD5-2555F56206A6
Creating your own snippets in Visual Studio Code
7/5/2018
It is easy to add code snippets to Visual Studio Code both for your own use or to share with others on the public Extension Marketplace. TextMate .tmSnippets files are supported.

Creating your own snippets

Code snippets are templates that make it easier to enter repeating code patterns, such as loops or conditional-statements.

Snippets show in IntelliSense (kb(editor.action.triggerSuggest)) mixed with other suggestions as well as in a dedicated snippet picker (Insert Snippet in the Command Palette). There is also support for tab-completion: Enable it with "editor.tabCompletion": true, type a snippet prefix, and press kb(insertSnippet) to insert a snippet.

The snippet syntax follows the TextMate snippet syntax with the exception of 'interpolated shell code', which is not supported.

ajax snippet

Add snippets from the Marketplace

Many extensions on the VS Code Marketplace include snippets. If you find one you want to use, install it and restart VS Code and the new snippet will be available (see here for more instructions on installing an extension).

Below are some popular extensions which include snippets in their language support:

Tip: The extensions shown above are dynamically queried. Click on an extension tile above to read the description and reviews to decide which extension is best for you. See more in the Marketplace.

Creating your own snippets

You can define your own snippets, either global snippets or snippets for a specific language. To open up a snippet file for editing, select User Snippets under File > Preferences (Code > Preferences on macOS) and select the language (by language identifier) for which the snippets should appear or create a new global snippet (New Global Snippets file...).

snippet dropdown

Snippets are defined in a JSON format. The example below is a For Loop snippet you would use for JavaScript:

{
    "For_Loop": {
        "prefix": "for",
        "body": [
          "for (const ${2:element} of ${1:array}) {",
          "\t$0",
          "}"
        ],
        "description": "For Loop"
    },
}

In the example above:

  • For Loop is the snippet name.
  • prefix defines how this snippet is selected from IntelliSense and tab completion. In this case for.
  • body is the content and either a single string or an array of strings of which each element will be inserted as separate line.
  • description is the description used in the IntelliSense drop down.

The example above has two placeholders, ${1:array} and ${2:element}. You can quickly traverse them in the order of their number. The string after the number and colon is used as an initial default.

Snippet filenames

The file type and name define if a snippet is global or specific to a language. Snippets stored in a JSON file that is named after a language identifier (<languageId>.json) are language specific. For example, JavaScript-only snippets go in a javascript.json file.

Global snippets

Global snippets that are applicable whenever you are editing and are stored in <name>.code-snippets files, for example MyGlobal.code-snippets. The JSON schema of global snippets allows you to define a scope property which can filter the languages (based on language identifier) for which a snippet is applicable.

The sample below is the For Loop again but this time it is scoped to JavaScript and TypeScript.

{
    "For_Loop": {
        "prefix": "for",
        "scope": "javascript,typescript",
        "body": [
          "for (const ${2:element} of ${1:array}) {",
          "\t$0",
          "}"
        ],
        "description": "For Loop"
    },
}

Once you have added a new snippet, you can try it out right away, no restart needed.

Snippet syntax

The body of a snippet can use special constructs to control cursors and the text being inserted. The following are supported features and their syntaxes:

Tabstops

With tabstops, you can make the editor cursor move inside a snippet. Use $1, $2 to specify cursor locations. The number is the order in which tabstops will be visited, whereas $0 denotes the final cursor position. Multiple occurrences of the same tabstop are linked and updated in sync.

Placeholders

Placeholders are tabstops with values, like ${1:foo}. The placeholder text will be inserted and selected such that it can be easily changed. Placeholders can be nested, like ${1:another ${2:placeholder}}.

Choice

Placeholders can have choices as values. The syntax is a comma separated enumeration of values, enclosed with the pipe-character, for example ${1|one,two,three|}. When the snippet is inserted and the placeholder selected, choices will prompt the user to pick one of the values.

Variables

With $name or ${name:default} you can insert the value of a variable. When a variable isn’t set, its default or the empty string is inserted. When a variable is unknown (that is, its name isn’t defined) the name of the variable is inserted and it is transformed into a placeholder.

The following variables can be used:

  • TM_SELECTED_TEXT The currently selected text or the empty string
  • TM_CURRENT_LINE The contents of the current line
  • TM_CURRENT_WORD The contents of the word under cursor or the empty string
  • TM_LINE_INDEX The zero-index based line number
  • TM_LINE_NUMBER The one-index based line number
  • TM_FILENAME The filename of the current document
  • TM_FILENAME_BASE The filename of the current document without its extensions
  • TM_DIRECTORY The directory of the current document
  • TM_FILEPATH The full file path of the current document
  • CLIPBOARD The contents of your clipboard

For inserting the current date and time:

  • CURRENT_YEAR The current year
  • CURRENT_YEAR_SHORT The current year's last two digits
  • CURRENT_MONTH The month as two digits (example '02')
  • CURRENT_MONTH_NAME The full name of the month (example 'July')
  • CURRENT_MONTH_NAME_SHORT The short name of the month (example 'Jul')
  • CURRENT_DATE The day of the month
  • CURRENT_DAY_NAME The name of day (example 'Monday')
  • CURRENT_DAY_NAME_SHORT The short name of the day (example 'Mon')
  • CURRENT_HOUR The current hour in 24-hour clock format
  • CURRENT_MINUTE The current minute
  • CURRENT_SECOND The current second

Variable transforms

Transformations allow you to modify the value of a variable before it is inserted. The definition of a transformation consists of three parts:

  1. A regular expression that is matched against the value of a variable, or the empty string when the variable cannot be resolved.
  2. A "format string" that allows to reference matching groups from the regular expression. The format string allows for conditional inserts and simple modifications.
  3. Options that are passed to the regular expression.

The following example inserts the name of the current file without its ending, so from foo.txt it makes foo.

${TM_FILENAME/(.*)\\..+$/$1/}
  |           |         |  |
  |           |         |  |-> no options
  |           |         |
  |           |         |-> references the contents of the first
  |           |             capture group
  |           |
  |           |-> regex to capture everything before
  |               the final `.suffix`
  |
  |-> resolves to the filename

Placeholder-Transform

Like a Variable-Transform, a transformation of a placeholder allows changing the inserted text for the placeholder when moving to the next tab stop. The inserted text is matched with the regular expression and the match or matches - depending on the options - are replaced with the specified replacement format text. Every occurrence of a placeholder can define its own transformation independently using the value of the first placeholder. The format for Placeholder-Transforms is the same as for Variable-Transforms.

Grammar

Below is the EBNF (extended Backus-Naur form) for snippets. With \ (backslash), you can escape $, } and \. Within choice elements, the backslash also escapes comma and pipe characters.

any         ::= tabstop | placeholder | choice | variable | text
tabstop     ::= '$' int
                | '${' int '}'
                | '${' int  transform '}'
placeholder ::= '${' int ':' any '}'
choice      ::= '${' int '|' text (',' text)* '|}'
variable    ::= '$' var | '${' var '}'
                | '${' var ':' any '}'
                | '${' var transform '}'
transform   ::= '/' regex '/' (format | text)+ '/' options
format      ::= '$' int | '${' int '}'
                | '${' int ':' '/upcase' | '/downcase' | '/capitalize' '}'
                | '${' int ':+' if '}'
                | '${' int ':?' if ':' else '}'
                | '${' int ':-' else '}' | '${' int ':' else '}'
regex       ::= JavaScript Regular Expression value (ctor-string)
options     ::= JavaScript Regular Expression option (ctor-options)
var         ::= [_a-zA-Z] [_a-zA-Z0-9]*
int         ::= [0-9]+
text        ::= .*

Using TextMate snippets

You can also use existing TextMate snippets (.tmSnippets) with VS Code. See the Using TextMate Snippets topic in our Extension Authoring section to learn more.

Assign keybindings to snippets

You can create custom keybindings to insert specific snippets. Open keybindings.json (Preferences: Open Keyboard Shortcuts File), which defines all your keybindings, and add a keybinding passing "snippet" as an extra argument:

{
  "key": "cmd+k 1",
  "command": "editor.action.insertSnippet",
  "when": "editorTextFocus",
  "args": {
    "snippet": "console.log($1)$0"
  }
}

The keybinding will invoke the Insert Snippet command but instead of prompting you to select a snippet, it will insert the provided snippet. You define the custom keybinding as usual with a keyboard shortcut, command id, and optional when clause context for when the keyboard shortcut is enabled.

Also, instead of using the snippet argument value to define your snippet inline, you can reference an existing snippet by using the langId and name arguments :

{
  "key": "cmd+k 1",
  "command": "editor.action.insertSnippet",
  "when": "editorTextFocus",
  "args": {
    "langId": "csharp",
    "name": "myFavSnippet"
  }
}

Next Steps

Common Questions

Q: What if I want to use existing TextMate snippets from a .tmSnippet file?

A: You can easily package TextMate snippets files for use in VS Code. See Using TextMate Snippets in our Extension Authoring documentation.