利用img和div标签实现图像下拉列表的模拟

 

dropdownlist本身不支持图像列表，那么我们利用jquery来实现下拉列表的模拟。

如图

image image image image

其实很简单，不用自定义控件之类，因为我们在mvc下不建议使用asp.net服务器控件，所以我们只用了div和img标签实现这个功能

1.首先介绍一下数据库表结构，这是下拉列表用到的数据

Code

用到的表

image image image

2.创建 company，department的录入窗体

如下图，因为不是重点，不再介绍，只要注意一点，company.id为自增int，注意属性窗口中auto Generated Value为true，Auto-Sync为OnInsert，这样linq才可没错

 

image image

code

        [AcceptVerbs(HttpVerbs.Post)]
        public ActionResult CreateCompany(string name, string brief)
        {
            string strResult = "失败";
            ServiceDataContext db = new ServiceDataContext();
            Company com = new Company();
            com.Name = name;
            com.Brief = brief;
            try
            {
                db.Companies.InsertOnSubmit(com);
                db.SubmitChanges();
                strResult = "成功";
            }
            catch
            {
                strResult = "失败，名称重复？";
            }
            return Json(strResult);
        }

3.设计下拉菜单（这才是我想说的重点）

 <td>
                    <img id="imgDefault" src='<%=ViewData["selectedUrl"]%>' class="imgCss" alt="" /><img
                        id="imgArrow" src="<%=ViewData["arrowUrl"]%>" class="DropdownCss" alt="" />
                    <div id="divList" class="scrolldivHidden">
                        <%=ViewData["imageTable"]%></div>
                    <%=Html.Hidden("head") %>
                </td>

这里selectedUrl为选择的图像，有默认值，arrowUrl为下拉图标，ViewData["imageTable"]是下拉列表框

这里用到的css

.Visible
{
    visibility: visible;
    display: block;
}
.Hidden
{
    visibility: hidden;
    display: none;
}
.imgCss
{
    cursor: hand;
    width: 18px;
    height: 18px;
    border: 1px solid #c3c3c3;
}
.DropdownCss
{
    cursor: hand;
    width: 9px;
    height: 9px;
    vertical-align: top;
}
.scrolldivHidden
{
    position:absolute;
    width: 36px;
    height: 50px;
    z-index: 1;
    left: 0px;
    top: 0x;
    overflow-y: auto;
    overflow-x:hidden;
    display:none;
}
.scrolldivVisible
{
    position:absolute;
    width: 36px;
    height: 50px;
    z-index: 1;
    left: 0px;
    top: 0x;
    overflow-y: auto;
    overflow-x:hidden;
    display:block;
}

主要我们用到jquery来实现选择等功能

这里用到jquery一个选择框的插件
/*
* Manipulation for HTML SELECT with jQuery
* Created by Baldwin (http://www.dnnsun.com)
* version: 1.0 (02/03/2009)
* @requires jQuery v1.2 or later
*/
; (function($) {
    /* Clear all options */
    $.fn.clearSelect = function() {
        return this.each(function() {
            if (this.tagName == 'SELECT') this.options.length = 0;
        });
    }

    /* Fill the options with the object array: [{'Text':'Hello','Value':'1'}]*/
    $.fn.fillSelect = function(data) {
        return this.clearSelect().each(function() {
            if (this.tagName == 'SELECT') {
                var dropdownList = this;
                if (data && data.length > 0) {
                    $.each(data, function(index, optionData) {
                        var option = new Option(optionData.Text, optionData.Value);

                        if ($.browser.msie)
                            dropdownList.add(option);
                        else
                            dropdownList.add(option, null);
                    });
                    dropdownList.disabled = false;
                }
                else
                    dropdownList.disabled = true;
            }
        });
    }

    /* loading when applying Ajax fillSelect */
    $.fn.loadSelect = function(loadText) {
        var data = [{ 'Text': loadText, 'Value': ''}];
        this.fillSelect(data);
    }

    /* selected the target option with value */
    $.fn.selected = function(value) {
        return this.each(function() {
            if (this.tagName == 'SELECT') {
                var options = this.options;
                if (options.length > 0) {
                    $.each(options, function(index, optionData) {
                        // once match then exist loop
                        if (optionData.value == value) {
                            optionData.selected = true;
                            return false;
                        }
                    });
                }
            }
        });
    }

    /* TODO:selected the target option with text */
    $.fn.selectedText = function(text) {
        return this.each(function() {
            if (this.tagName == 'SELECT') {
                var options = this.options;
                if (options.length > 0) {
                    $.each(options, function(index, optionData) {
                        // once match then exist loop
                        if (optionData.text == text) {
                            optionData.selected = true;
                            return false;
                        }
                    });
                }
            }
        });
    }

    /* returns the selected value */
    $.fn.getSelected = function() {
        return $(this).val();
    }

    /* return the text of selected option */
    $.fn.getSelectedText = function() {
        return $(this).children("[@selected]").text();
    }
})(jQuery);

 

function getDepartment(data) { $("#department").fillSelect(data); }

$("#company").change(function() {
                $.getJSON("GetDepartment?company=" + $("#company").val(), null, getDepartment);
            });

实现了联动框

下面的代码实现了下拉和选择功能

          $("#imgArrow,#imgDefault").toggle(function() {
                $("#divList").css("left", $("#imgDefault").css("left"));
                $("#divList").slideToggle("fast");
            }, function() {
                $("#divList").css("left", $("#imgDefault").css("left"));
                $("#divList").slideToggle("fast");
            });
            $("#head").val($("#imgDefault").attr("src"));
            $("img:.imgList").click(function() {
                $("#imgDefault").attr("src", $(this).attr("src"));
                $("#divList").slideToggle("fast");
                $("#head").val($("#imgDefault").attr("src"));
            }).hover(function() {
                $(this).removeClass().addClass("alpha");
            }, (function() {
                $(this).removeClass();
            }));
            $("body").click(function() {
                $("#divList").slideUp("fast");
                $("#imgDefault").hover(function() {
                    $(this).addClass("alpha");
                }, function() {
                    $(this).removeClass();
                });
            });

还有我们用到的action

  public ActionResult CreateService()
        {
            ViewData["company"] = GetCompanyList();
            List<SelectListItem> blank=new List<SelectListItem>();
            blank.Add(GetBlankDepartment());
            ViewData["department"] =  blank.ToArray();
            ViewData["head"] = GetHeadList();
            ViewData["selectedUrl"] = Url.Content(Head_Folder + "Head/head0.gif");
            ViewData["arrowUrl"] = Url.Content(Head_Folder + "/dropdown.gif");
            ViewData["imageTable"] = GetImageTable();
            return View();
        } 
  [AcceptVerbs(HttpVerbs.Get)]
        public ActionResult GetDepartment(int? company)
        {
            SelectListItem[] items=null;
            if(company!=null)
               items = GetDepartmentList((int)company);
            else
            {
                SelectListItem i=GetBlankDepartment();
                items=new SelectListItem[]{i};
            }
            return Json(items);
        }
      private SelectListItem[] GetCompanyList()
        {
            ServiceDataContext db = new ServiceDataContext();
            var items = from t in db.Companies
                        select new
                        {
                            ID = t.ID,
                            Name = t.Name,
                            Brief = t.Brief
                        };
            List<SelectListItem> s = new List<SelectListItem>();
            SelectListItem b = new SelectListItem();
            b.Text = "--please select company--";
            b.Value = "";
            s.Add(b);
            foreach (var i in items)
            {
                SelectListItem item = new SelectListItem();
                item.Text = i.Name;
                item.Value = i.ID.ToString();
                s.Add(item);
            }
            return s.ToArray();
        }

        private SelectListItem[] GetDepartmentList(int nCompanyId)
        {

            ServiceDataContext db = new ServiceDataContext();
            var items = from t in db.Departments
                        where t.Company==nCompanyId
                        select new
                        {
                            ID = t.ID,
                            Name = t.Name,
                            Brief = t.Brief
                        };
            List<SelectListItem> s = new List<SelectListItem>();
            SelectListItem b = new SelectListItem();
            b.Text = "--please select department--";
            b.Value = "";
            s.Add(b);
            foreach (var i in items)
            {
                SelectListItem item = new SelectListItem();
                item.Text = i.Name;
                item.Value = i.ID.ToString();
                s.Add(item);
            }
            return s.ToArray();
        }

        private string[] GetHeadList()
        {
            List<string> head = new List<string>();
            string strServer=Url.Content("~/Content/images/Head/");
            string strUrlFolder = Server.MapPath(Url.Content(Head_Folder+"Head/"));
            string[] fileEntries = Directory.GetFiles(strUrlFolder);
            FileInfo fi=null;
            foreach (string file in fileEntries)
            {
                fi =  new FileInfo(file);
                if (fi.Name.ToLower().IndexOf("head")==0 && !fi.FullName.ToLower().Contains("_offline"))
                {
                    head.Add(strServer+fi.Name);
                }
            }
            return head.ToArray();
        }

        private string GetImageTable()
        {
            System.Text.StringBuilder sbResult = new System.Text.StringBuilder();
            string[] arrImgs = GetHeadList();
            foreach (string strImage in arrImgs)
            {
                string strFile=strImage.Substring(strImage.LastIndexOf("/")+1);
                sbResult.AppendLine(string.Format("<img id='{0}' src='{1}' class='imgList' /></br>",
                    "img_"+strFile.Remove(strFile.LastIndexOf(".")),
                    Url.Content(strImage)
                    ));
            }
            string strImg=sbResult.ToString();
            strImg=strImg.Remove(strImg.Length-5,5);
            return strImg;
        }
    }

注意紫色处，我们加了cssimgList来供jquery选择

 $("img:.imgList").click(function() {
                $("#imgDefault").attr("src", $(this).attr("src"));
                $("#divList").slideToggle("fast");
                $("#head").val($("#imgDefault").attr("src"));
            }).hover(function() {
                $(this).removeClass().addClass("alpha");
            }, (function() {
                $(this).removeClass();
            }));
好了效果试一下吧，完整代码见我的个人网站 mvcMembership.RAR[对了，现在只能保证白天开机，毕竟我自己的机器不能一天到晚开着 ，哎，找不到工作，只能独自在家研究

代码下载

posted @ 2009-06-11 09:34  柯南  阅读(2510)  评论(25)    收藏  举报