问Window.close在页面引用Apex方法中不工作

EN

public PageReference savePostSurveyAnswer(){
        String sitePathPrefix = Site.getPathPrefix();
        System.debug('savePostSurveyAnswer method start');

        CaseIdentifierIdValue = ApexPages.currentPage().getParameters().get('caseIdentifierId');


        ShGl_PostChatSurvey__c postChatSurvey = new ShGl_PostChatSurvey__c(); 
        postChatSurvey.ShGl_SurveyQuestion1__c = question1;
        postChatSurvey.ShGl_SurveyQuestion2__c = question2;
        postChatSurvey.ShGl_SurveyQuestion3__c = question3;
        postChatSurvey.ShGl_SurveyQuestion4__c = question4;
        postChatSurvey.ShGl_SurveyResponse1__c = questionAnsSelected1; 
        postChatSurvey.ShGl_SurveyResponse2__c = questionAnsSelected2; 
        postChatSurvey.ShGl_SurveyResponse3__c = questionAnsSelected3; 
        postChatSurvey.ShGl_SurveyResponse4__c = questionAnsSelected4; 
        postChatSurvey.ShGl_Market_Code__c = 'US'; //new data base model
        postChatSurvey.ShGl_UniqueCaseIdentifier__c = CaseIdentifierIdValue;
        //postChatSurvey.ShGl_LiveTranscriptChatKey__c = chatKeyIdValue;
        //postChatSurvey.ShGl_CaseOfSurvey__c = (Id) LiveChatTranscriptObj.CaseId;   //through trigger     
        Database.SaveResult postSaveResult = Database.insert(postChatSurvey);
        return new PageReference('javascript:window.close();');
}