以上这些都不起作用。真正有效的解决方案是：

$(function(){
  //this is your dialog:
  $('#mydiv').dialog({
    // Step 1. Add an extra class to our dialog to address the dialog directly. Make sure that this class is not used anywhere else:
    dialogClass: 'my-extra-class' 
  })
  // Step 2. Hide the close 'X' button on the dialog that you marked with your extra class
  $('.my-extra-class').find('.ui-dialog-titlebar-close').css('display','none');
  // Step 3. Enjoy your dialog without the 'X' link
})

请检查它是否适合您。

隐藏按钮的最佳方法是使用其数据图标属性对其进行过滤：

$('#dialog-id [data-icon="delete"]').hide();

您也可以删除标题行：

<div data role=“header”></分区>

其移除关闭按钮。

http://jsfiddle.net/marcosfromero/aWyNn/

$('#yourdiv').                 // Get your box ...
  dialog().                    // ... and turn it into dialog (autoOpen: false also works)
  prev('.ui-dialog-titlebar'). // Get title bar,...
  find('a').                   // ... then get the X close button ...
  hide();                      // ... and hide it

一旦对元素调用了.dialog（），就可以在任何方便的时候找到关闭按钮（和其他对话框标记），而无需使用事件处理程序：

$("#div2").dialog({                    // call .dialog method to create the dialog markup
    autoOpen: false
});
$("#div2").dialog("widget")            // get the dialog widget element
    .find(".ui-dialog-titlebar-close") // find the close button for this dialog
    .hide();                           // hide it

替代方法：

在对话框事件处理程序中，这是指“dialogged”元素，$（this）.parent（）是指对话框标记容器，因此：

$("#div3").dialog({
    open: function() {                         // open event handler
        $(this)                                // the element being dialogged
            .parent()                          // get the dialog widget element
            .find(".ui-dialog-titlebar-close") // find the close button for this dialog
            .hide();                           // hide it
    }
});

仅供参考，对话框标记如下所示：

<div class="ui-dialog ui-widget ui-widget-content ui-corner-all ui-draggable ui-resizable">
    <!-- ^--- this is the dialog widget -->
    <div class="ui-dialog-titlebar ui-widget-header ui-corner-all ui-helper-clearfix">
        <span class="ui-dialog-title" id="ui-dialog-title-dialog">Dialog title</span>
        <a class="ui-dialog-titlebar-close ui-corner-all" href="#"><span class="ui-icon ui-icon-closethick">close</span></a>
    </div>
    <div id="div2" style="height: 200px; min-height: 200px; width: auto;" class="ui-dialog-content ui-widget-content">
        <!-- ^--- this is the element upon which .dialog() was called -->
    </div>
</div>

此处演示

以上这些都不起作用。真正有效的解决方案是：

$(function(){
  //this is your dialog:
  $('#mydiv').dialog({
    // Step 1. Add an extra class to our dialog to address the dialog directly. Make sure that this class is not used anywhere else:
    dialogClass: 'my-extra-class' 
  })
  // Step 2. Hide the close 'X' button on the dialog that you marked with your extra class
  $('.my-extra-class').find('.ui-dialog-titlebar-close').css('display','none');
  // Step 3. Enjoy your dialog without the 'X' link
})

请检查它是否适合您。