javascript - CodeMirror:从按钮折叠全部或展开全部？

Question

我想在 codemirror textarea 周围设置按钮，允许用户通过单击按钮展开全部或全部折叠。这将避免他们不得不学习捷径。可能吗？

这是编辑器的定义(extraKeys 的功能符合预期):

    var editor = CodeMirror.fromTextArea(document.getElementById("xmlViewer"), {
    mode: "text/html",
    lineNumbers: true,
    tabMode: 'indent',
    lineWrapping: true,
    autoCloseTags: true,
    height: "650px",
    width: "90%",
    parserfile: "parsexml.js",
    stylesheet: "css/xmlcolors.css",
    path: "js/",
    continuousScanning: 500,
    extraKeys: {
        "Ctrl-Q": function (cm) { cm.foldCode(cm.getCursor()); },
        "Alt-F": "findPersistent",
        "Ctrl-Y": "foldAll",
        "Ctrl-I": "unfoldAll"
    },
    foldGutter: true,
    autoRefresh: true,
    gutters: ["CodeMirror-linenumbers", "CodeMirror-foldgutter"]
});

这是按钮的定义:

<input type="button" id="expandAllBtn" value="Expand All" class="btn btn-outline-primary btn-sm" />

这里是 onclick 的定义:

$("#collapseAllBtn").on("click", function (e) {

        editor.foldAll; // nothing happens
        //editor.foldAll(); // error not a function
        //editor.commands.foldAll(); // cannot read property of undefined
        //editor.commands.foldAll; // cannot read property of undefined
    });

Answer 1

下面是实现这个的方法:

$("#collapseAllBtn").on("click", function (e) {

        editor.execCommand("foldAll");

    });