Question

如果用户注意离开包含未保存设置的页面，我希望显示警告，但显然不是在他们尝试保存这些设置时。

我想我的理解是错误的，因为我认为下面应该有效，但事实并非如此。有人能告诉我我做错了什么吗？感谢。

$('input[name="Submit"]').off('onbeforeunload');

window.onbeforeunload = function closeEditorWarning(){

    /** Check to see if the settings warning is displayed */
    if($('#unsaved-settings').css('display') !== 'none'){
        bol_option_changed = true;
    }

    /** Display a warning if the user is trying to leave the page with unsaved settings */
    if(bol_option_changed === true){
        return '';
    }


};

Answer 1

您可以使用jquery .on（）设置onbeforeunload，然后在表单提交中使用.off（）

// Warning
$(window).on('beforeunload', function(){
    return "Any changes will be lost";
});

// Form Submit
$(document).on("submit", "form", function(event){
    // disable unload warning
    $(window).off('beforeunload');
});

Answer 2

你可以试试这个：点击提交按钮时设置一个标志，并使用此标志检查用户是否已点击提交或中途离开页面

伪代码：

var submit_clicked = false;

$('input[name="Submit"]').click(function(){
    submit_clicked = true;
});


window.onbeforeunload = function closeEditorWarning () {

  /** Check to see if the settings warning is displayed */
  if(($('#unsaved-settings').css('display') !== 'none') && 
      submit_clicked === false) {
    bol_option_changed = true;
  }

  /** Display a warning if the user is trying to leave the page with unsaved settings */
  if(bol_option_changed === true){
    return '';
  }


};

Answer 3

Here is the perfect answer for your question.

document.querySelector('.send').addEventListener("click", function(){ // put a class="send" in submit button
    window.btn_clicked = true; // if it is click onbeforeunload will not add dialog anymore
});
window.onbeforeunload = function(){

      if(!window.btn_clicked){
          var lot = $('#lot_no').val(); //getting values from form
      if(!lot == ''){  //checking if it is not empty
        return 'Changes you made not be saved!';
      }

      }


};

离开页面时显示带有'onbeforeunload'的警告，除非单击“提交”

3 个答案: