仅当选中了文字后，才显示右键菜单

package.json

@@ -93,6 +93,7 @@
           "group": "1_modification@9"
         },
         {
+          "when": "editorTextFocus && _textSelectionLength >= 1",
           "submenu": "extension.stringConversionMenu",
           "group": "1_modification@9"
         }

src/extension.ts

@@ -21,6 +21,12 @@ export function activate(context: vscode.ExtensionContext) {
 	// 	vscode.window.showInformationMessage('Hello World from text-conversion!');
 	// });
 
+	// 用于判断是否展示右键菜单
+	vscode.window.onDidChangeTextEditorSelection(event => {
+		const text = event.textEditor.document.getText(event.selections[0]);
+		vscode.commands.executeCommand('setContext', '_textSelectionLength', text.length);
+	});
+
 	const handleEditorReplace = (convertFunction: ConvertFunction) => {
 		// 获取当前编辑器
 		let editor = vscode.window.activeTextEditor;