用什么封装?这里只是用了TagHelper,是啥?自己瞅文档去
在学习使用TagHelper的时候,最希望的就是能有个Demo能够让自己作为参考
- 怎么去封装一个组件?
- 不同的情况怎么去实现?
- 有没有更好更高效的方法?
找啊找啊找,最后跑去看了看mvc中的TagHelpers,再好好瞅了瞅TagHelper的文档
勉强折腾了几个组件出来,本来想一个组件一个组件写文章的,但是发现国庆已经结束了~
效果预览
代码仅供参考,有不同的意见也忘不吝赐教
Checkbox复选框组件封装
标签名称:cl-checkbox
标签属性: asp-for:绑定的字段,必须指定
- asp-items:绑定单选项 类型为:IEnumerable<SelectListItem>
- asp-skin:layui的皮肤样式,默认or原始
- asp-title:若只是一个复选框时显示的文字,且未指定items,默认Checkbox的值为true
其中在封装的时候看源代码发现两段非常有用的代码
1.判断是否可以多选:
var realModelType = For.ModelExplorer.ModelType; //通过类型判断是否为多选 var _allowMultiple = typeof(string) != realModelType && typeof(IEnumerable).IsAssignableFrom(realModelType);
2.获取模型绑定的列表值(多选的情况)
var currentValues = Generator.GetCurrentValues(ViewContext,For.ModelExplorer,expression: For.Name,allowMultiple: true);
这3句代码是在mvc自带的SelectTagHelper中发现的.
因为core其实已经提供了非常多的TagHelper,比如常用的select就是很好的参考对象,封装遇到问题的时候去找找看指不定就又意外的收获.
CheckboxTagHelper代码
using System.Collections.Generic; using Microsoft.AspNetCore.Mvc.Rendering; using Microsoft.AspNetCore.Mvc.ViewFeatures; using Microsoft.AspNetCore.Razor.TagHelpers; namespace LayuiTagHelper.TagHelpers { /// <summary> /// 复选框 /// </summary> /// <remarks> /// 当Items为空时显示单个,且选择后值为true /// </remarks> [HtmlTargetElement(CheckboxTagName)] public class CheckboxTagHelper : TagHelper { private const string CheckboxTagName = "cl-checkbox"; private const string ForAttributeName = "asp-for"; private const string ItemsAttributeName = "asp-items"; private const string SkinAttributeName = "asp-skin"; private const string SignleTitleAttributeName = "asp-title"; protected IHtmlGenerator Generator { get; } public CheckboxTagHelper(IHtmlGenerator generator) { Generator = generator; } [ViewContext] public ViewContext ViewContext { get; set; } [HtmlAttributeName(ForAttributeName)] public ModelExpression For { get; set; } [HtmlAttributeName(ItemsAttributeName)] public IEnumerable<SelectListItem> Items { get; set; } [HtmlAttributeName(SkinAttributeName)] public CheckboxSkin Skin { get; set; } = CheckboxSkin.默认; [HtmlAttributeName(SignleTitleAttributeName)] public string SignleTitle { get; set; } public override void Process(TagHelperContext context, TagHelperOutput output) { //获取绑定的生成的Name属性 string inputName = ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For?.Name); string skin = string.Empty; #region 风格 switch (Skin) { case CheckboxSkin.默认: skin = ""; break; case CheckboxSkin.原始: skin = "primary"; break; } #endregion #region 单个复选框 if (Items == null) { output.TagName = "input"; output.TagMode = TagMode.SelfClosing; output.Attributes.Add("type", "checkbox"); output.Attributes.Add("id", inputName); output.Attributes.Add("name", inputName); output.Attributes.Add("lay-skin", skin); output.Attributes.Add("title", SignleTitle); output.Attributes.Add("value", "true"); if (For?.Model?.ToString().ToLower() == "true") { output.Attributes.Add("checked", "checked"); } return; } #endregion #region 复选框组 var currentValues = Generator.GetCurrentValues(ViewContext,For.ModelExplorer,expression: For.Name,allowMultiple: true); foreach (var item in Items) { var checkbox = new TagBuilder("input"); checkbox.TagRenderMode = TagRenderMode.SelfClosing; checkbox.Attributes["type"] = "checkbox"; checkbox.Attributes["id"] = inputName; checkbox.Attributes["name"] = inputName; checkbox.Attributes["lay-skin"] = skin; checkbox.Attributes["title"] = item.Text; checkbox.Attributes["value"] = item.Value; if (item.Disabled) { checkbox.Attributes.Add("disabled", "disabled"); } if (item.Selected || (currentValues != null && currentValues.Contains(item.Value))) { checkbox.Attributes.Add("checked", "checked"); } output.Content.AppendHtml(checkbox); } output.TagName = ""; #endregion } } public enum CheckboxSkin { 默认, 原始 } }
使用示例
@{ string sex="男"; var Items=new List<SelectListItem>() { new SelectListItem() { Text = "男", Value = "男" }, new SelectListItem() { Text = "女", Value = "女"}, new SelectListItem() { Text = "不详", Value = "不详",Disabled=true } }; } <cl-checkbox asp-items="Model.Items" asp-for="Hobby1" asp-skin="默认"></cl-checkbox> <cl-checkbox asp-for="Hobby3" asp-title="单个复选框"></cl-checkbox>
Radio单选框组件封装
标签名称:cl-radio
- 标签属性: asp-for:绑定的字段,必须指定
- asp-items:绑定单选项 类型为:IEnumerable<SelectListItem>
太简单了,直接上代码了
RadioTagHelper代码
using System; using System.Collections.Generic; using Microsoft.AspNetCore.Mvc.Rendering; using Microsoft.AspNetCore.Mvc.ViewFeatures; using Microsoft.AspNetCore.Razor.TagHelpers; namespace LayuiTagHelper.TagHelpers { /// <summary> /// 单选框 /// </summary> [HtmlTargetElement(RadioTagName)] public class RadioTagHelper : TagHelper { private const string RadioTagName = "cl-radio"; private const string ForAttributeName = "asp-for"; private const string ItemsAttributeName = "asp-items"; [ViewContext] public ViewContext ViewContext { get; set; } [HtmlAttributeName(ForAttributeName)] public ModelExpression For { get; set; } [HtmlAttributeName(ItemsAttributeName)] public IEnumerable<SelectListItem> Items { get; set; } public override void Process(TagHelperContext context, TagHelperOutput output) { if (For == null) { throw new ArgumentException("必须绑定模型"); } foreach (var item in Items) { var radio = new TagBuilder("input"); radio.TagRenderMode = TagRenderMode.SelfClosing; radio.Attributes.Add("id", ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For.Name)); radio.Attributes.Add("name", ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For.Name)); radio.Attributes.Add("value", item.Value); radio.Attributes.Add("title", item.Text); radio.Attributes.Add("type", "radio"); if (item.Disabled) { radio.Attributes.Add("disabled", "disabled"); } if (item.Selected || item.Value == For.Model?.ToString()) { radio.Attributes.Add("checked", "checked"); } output.Content.AppendHtml(radio); } output.TagName = ""; } } }
使用示例
@{ string sex="男"; var Items=new List<SelectListItem>() { new SelectListItem() { Text = "男", Value = "男" }, new SelectListItem() { Text = "女", Value = "女"}, new SelectListItem() { Text = "不详", Value = "不详",Disabled=true } }; } <cl-radio asp-items="@Items" asp-for="sex"></cl-radio>
最后再来一个开关组件
单个复选框其实可以直接用开关代替,恰巧layui中也有,于是也将开关单独的封装了一下,代码大同小异
就这个
使用也简单: <cl-switch asp-for="Hobby4" asp-switch-text="开启|关闭"></cl-switch>
namespace LayuiTagHelper.TagHelpers { /// <summary> /// 开关 /// </summary> [HtmlTargetElement(SwitchTagName)] public class SwitchTagHelper : TagHelper { private const string SwitchTagName = "cl-switch"; private const string ForAttributeName = "asp-for"; private const string SwitchTextAttributeName = "asp-switch-text"; protected IHtmlGenerator Generator { get; } public SwitchTagHelper(IHtmlGenerator generator) { Generator = generator; } [ViewContext] public ViewContext ViewContext { get; set; } [HtmlAttributeName(ForAttributeName)] public ModelExpression For { get; set; } [HtmlAttributeName(SwitchTextAttributeName)] public string SwitchText { get; set; } = "ON|OFF"; public override void Process(TagHelperContext context, TagHelperOutput output) { string inputName = ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(For?.Name); output.TagName = "input"; output.TagMode = TagMode.SelfClosing; if (For?.Model?.ToString().ToLower() == "true") { output.Attributes.Add("checked", "checked"); } output.Attributes.Add("type", "checkbox"); output.Attributes.Add("id", inputName); output.Attributes.Add("name", inputName); output.Attributes.Add("value", "true"); output.Attributes.Add("lay-skin", "switch"); output.Attributes.Add("lay-text", SwitchText); } } }
总结
封装的还很粗糙,正常的使用是没问题的,若发现问题,还望指出。
因为layui是直接在页面加载后渲染的表单标签,故没有多少和layui相关的样式。
除了一些表单组件之外,其实还对选项卡,时间轴,分页,代码显示组件做了一些封装,这些后面再介绍了。
当然,有兴趣的朋友可以先去一睹为快看看都实现了哪些组件
WeDemo分支clone命令:git clone https://git.coding.net/yimocoding/WeDemo.git -b LayuiTagHelper
选项卡,时间轴,分页,代码显示等Demo打包下载
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持阿兔在线工具。