根据HTML规范,HTML中的select标签没有readonly属性,只有disabled属性。所以如果你想让用户不改变下拉菜单,你必须使用disabled。

唯一的问题是禁用的HTML表单输入不会包含在POST / get数据中。

什么是最好的方法来模拟一个选择标签的只读属性,仍然得到POST数据?


当前回答

在IE中,我可以通过双击来击败onfocus=>onblur方法。 但是记住值,然后在onchange事件中恢复它似乎可以解决这个问题。

<select onfocus="this.oldvalue=this.value;this.blur();" onchange="this.value=this.oldvalue;">
....
</select>

你可以使用javascript变量来做类似的事情,而不需要expando属性。

其他回答

这是最简单、最好的解决办法。 您将在您的选择上设置一个readolny属性,或任何其他属性,如data-readonly,并执行以下操作

$("select[readonly]").live("focus mousedown mouseup click",function(e){
    e.preventDefault();
    e.stopPropagation();
});

我们还可以禁用除所选选项之外的所有选项。

这样,下拉菜单仍然可以工作(并提交其值),但用户不能选择其他值。

Demo

<选择> <选项禁用> 1 > < /选项 <选项> 2 > < /选项 <选项禁用> 3 < /选项> < /选择>

我知道这不会帮助每个人(如果你只是客户端),但会帮助一些全栈和控制后端以及前端的人。

如果用户没有编辑字段的特权,我只返回下拉列表的当前选择。

以下是我的后端控制器:

        #region Prepare Action Priviledges
        editAuditVM.ExtAuditEditRoleMatrixVM = new ExtAuditEditRoleMatrixVM
        {
            CanEditAcn = _extAuditEditRoleMatrixHelper.CanEditAcn(user, audit),
            CanEditSensitiveDesignation = _extAuditEditRoleMatrixHelper.CanEditSensitiveDesignation(user, audit),
            CanEditTitle = _extAuditEditRoleMatrixHelper.CanEditTitle(),
            CanEditAuditScope = _extAuditEditRoleMatrixHelper.CanEditAuditScope(user, audit)
        };
        #endregion


        #region Prepare SelectLists for Drop Downs
        #region AuditScope List
        IQueryable<SelectListItem> auditScopes = _auditTypesRepo.AuditTypes
            .Where(at => at.AuditTypeClassCode.ToLower() == "e")
            .Select(at => new SelectListItem
            { Text = at.AuditTypeText, Value = at.AuditTypeID.ToString() });
        // Cannot make a select readonly on client side.
        //  So only return currently selected option.
        if (!editAuditVM.ExtAuditEditRoleMatrixVM.CanEditAuditScope)
        {
            auditScopes = auditScopes
                .Where(ascopeId => ascopeId.Value == editAuditVM.ExternalAudit.AuditTypeID.ToString());
        }
        #endregion
        #endregion

一种简单的服务器端方法是删除所有选项,只删除希望被选中的选项。因此,在Zend Framework 1.12中,如果$element是一个Zend_Form_Element_Select:

 $value =  $element->getValue();
 $options = $element->getAttrib('options');
 $sole_option = array($value => $options[$value]);
 $element->setAttrib('options', $sole_option);

当您计划将选择设置为只读时,请将选择设置为禁用,然后在提交表单之前删除禁用属性。

// global variable to store original event/handler for save button
var form_save_button_func = null;

// function to get jQuery object for save button
function get_form_button_by_id(button_id) {
    return jQuery("input[type=button]#"+button_id);
}

// alter value of disabled element
function set_disabled_elem_value(elem_id, value)  {
    jQuery("#"+elem_id).removeAttr("disabled");
    jQuery("#"+elem_id).val(value);
    jQuery("#"+elem_id).attr('disabled','disabled');
}

function set_form_bottom_button_save_custom_code_generic(msg) {
    // save original event/handler that was either declared
    // through javascript or html onclick attribute
    // in a global variable
    form_save_button_func = get_form_button_by_id('BtnSave').prop('onclick'); // jQuery 1.6
    //form_save_button_func = get_form_button_by_id('BtnSave').prop('onclick'); // jQuery 1.7

    // unbind original event/handler (can use any of following statements below)
    get_form_button_by_value('BtnSave').unbind('click');
    get_form_button_by_value('BtnSave').removeAttr('onclick');

    // alternate save code which also calls original event/handler stored in global variable
    get_form_button_by_value('BtnSave').click(function(event){
        event.preventDefault();
        var confirm_result = confirm(msg);
        if (confirm_result) {
            if (jQuery("form.anyForm").find('input[type=text], textarea, select').filter(".disabled-form-elem").length > 0) {
                jQuery("form.anyForm").find('input[type=text], textarea, select').filter(".disabled-form-elem").removeAttr("disabled");
            }

            // disallow further editing of fields once save operation is underway
            // by making them readonly
            // you can also disallow form editing by showing a large transparent
            // div over form such as loading animation with "Saving" message text
            jQuery("form.anyForm").find('input[type=text], textarea, select').attr('ReadOnly','True');

            // now execute original event/handler
            form_save_button_func();
        }
    });
}

$(document).ready(function() {
    // if you want to define save button code in javascript then define it now

    // code below for record update
    set_form_bottom_button_save_custom_code_generic("Do you really want to update this record?");
    // code below for new record
    //set_form_bottom_button_save_custom_code_generic("Do you really want to create this new record?");

    // start disabling elements on form load by also adding a class to identify disabled elements
    jQuery("input[type=text]#phone").addClass('disabled-form-elem').attr('disabled','disabled');
    jQuery("input[type=text]#fax").addClass('disabled-form-elem').attr('disabled','disabled');
    jQuery("select#country").addClass('disabled-form-elem').attr('disabled','disabled');
    jQuery("textarea#address").addClass('disabled-form-elem').attr('disabled','disabled');

    set_disabled_elem_value('phone', '123121231');
    set_disabled_elem_value('fax', '123123123');
    set_disabled_elem_value('country', 'Pakistan');
    set_disabled_elem_value('address', 'address');

}); // end of $(document).ready function