如何使用自定义按钮发布到Suitelet？

/**
 * @NApiVersion 2.x
 * @NScriptType Suitelet
 */
define(['N/ui/serverWidget'], function(ui) {
    function onRequest(context) {
        if (context.request.method === 'GET') {
            var form = ui.createForm({
                title: 'Custom Suitelet'
            });

            // 添加一个自定义按钮
            form.addSubmitButton({
                label: '发布',
                functionName: 'customSubmit'
            });

            context.response.writePage(form);
        }
    }

    return {
        onRequest: onRequest
    };
});

/**
 * @NApiVersion 2.x
 * @NScriptType Suitelet
 */
define(['N/ui/serverWidget', 'N/log'], function(ui, log) {
    function onRequest(context) {
        if (context.request.method === 'GET') {
            var form = ui.createForm({
                title: 'Custom Suitelet'
            });

            // 添加一个自定义按钮
            form.addSubmitButton({
                label: '发布',
                functionName: 'customSubmit'
            });

            context.response.writePage(form);
        } else if (context.request.method === 'POST') {
            // 处理按钮点击事件
            handleCustomSubmit(context);
        }
    }

    function handleCustomSubmit(context) {
        try {
            // 在这里执行发布逻辑
            log.debug('Custom Submit', 'Button clicked!');

            // 示例：保存数据到记录
            var record = context.request.parameters.recordId;
            if (record) {
                var rec = record.load({ type: record.Type, id: record.id });
                rec.setValue({ fieldId: 'custrecord_status', value: 'Published' });
                rec.save();
            }

            context.response.write('发布成功！');
        } catch (e) {
            log.error('Custom Submit Error', e.message);
            context.response.write('发布失败：' + e.message);
        }
    }

    return {
        onRequest: onRequest
    };
});