npm install -g yo generator-code

yo code

code .

npm i vsce -g

"publisher": "zhenlei",

vsce package

yo code

code .

yarn add xslt-processor

declare module 'xslt-processor';

	"activationEvents": [
		"onCommand:zlxslt.runMyXSLT"
	],

// The module 'vscode' contains the VS Code extensibility API
// Import the module and reference it with the alias vscode in your code below
import * as vscode from 'vscode';
import * as fs from 'fs';
import { xmlParse, xsltProcess } from 'xslt-processor';
// this method is called when your extension is activated
// your extension is activated the very first time the command is executed
export function activate(context: vscode.ExtensionContext) {

	// Use the console to output diagnostic information (console.log) and errors (console.error)
	// This line of code will only be executed once when your extension is activated
	console.log('Congratulations, your extension "zlxslt" is now active!');

	const mydisposable: vscode.Disposable = vscode.commands.registerCommand('zlxslt.runMyXSLT', async (): Promise<any> => {
        const xsltFile = await vscode.window.showOpenDialog(
            {
                canSelectFiles: true,
                canSelectFolders: false,
                canSelectMany: false,
                filters: {
                    'XSLT' : ['xsl','xslt']
                }
            }
        );
        if(vscode.window.activeTextEditor !== undefined && xsltFile !== undefined) {
            const xml: string = vscode.window.activeTextEditor.document.getText();
            const xslt: string = fs.readFileSync(xsltFile[0].fsPath).toString();
            try {
                const rXml = xmlParse(xml);
                const rXslt = xmlParse(xslt);
                const result = xsltProcess(rXml, rXslt);
                const textDoc = await vscode.workspace.openTextDocument(
                    {
                        content: result,
                        language: 'xml'
                    }
                );
                
                vscode.window.showTextDocument(textDoc, vscode.ViewColumn.Beside);
           
                
            }
            catch(e) {
                vscode.window.showErrorMessage(e);
            }
        }
        else {
            vscode.window.showErrorMessage('An error occurred while accessing the XML and/or XSLT source files. Please be sure the active window is XML, and you have selected an appropriate XSLT file.');
        }
    });

	context.subscriptions.push(mydisposable);
}

// this method is called when your extension is deactivated
export function deactivate() {}