Flexibly master the use of GridView in Asp.net MVC
This tutorial shares the usage method and specific implementation code of the GridView control for your reference. The specific content is as follows
The entity class under the Models file:
public class Customer { public int Id { get; set; } public string CompanyName { get; set; } public string ContactTitle { get; set; } public string Address { get; set; } public string City { get; set; } public string Country { get; set; } public string Phone { get; set; } public DateTime Founded { get; set; } }
public class CustomersViewModel { public IQueryable<Customer> Customers { get; set; } public PagingInfo PagingInfo { get; set; } public string JsonPagingInfo { get; set; } }
public static class ExpresssionBuilder { private static readonly MethodInfo containsMethod = typeof(string).GetMethod("Contains"); private static readonly MethodInfo startsWithMethod = typeof(string).GetMethod("StartsWith", new Type[] { typeof(string) }); private static readonly MethodInfo endsWithMethod = typeof(string).GetMethod("EndsWith", new Type[] { typeof(string) }); public static Expression<Func<T,bool>> GetExpression<T>(IList<FilterObject> filters) { if (filters.Count == 0) return null; ParameterExpression param = Expression.Parameter(typeof(T), "t"); Expression exp = null; if (filters.Count == 1) exp = GetExpression<T>(param, filters[0]); else if (filters.Count == 2) exp = GetExpression<T>(param, filters[0], filters[1]); else { while (filters.Count > 0) { var f1 = filters[0]; var f2 = filters[1]; if (exp == null) exp = GetExpression<T>(param, filters[0], filters[1]); else exp = Expression.AndAlso(exp, GetExpression<T>(param, filters[0], filters[1])); filters.Remove(f1); filters.Remove(f2); if (filters.Count == 1) { exp = Expression.AndAlso(exp, GetExpression<T>(param, filters[0])); filters.RemoveAt(0); } } } return Expression.Lambda<Func<T, bool>>(exp, param); } private static Expression GetExpression<T>(ParameterExpression param, FilterObject filter) { MemberExpression member = Expression.Property(param, filter.Column); //ConstantExpression constant = Expression.Constant(filter.Value); //新的逻辑来处理可空Decimal和DateTime值 UnaryExpression constant = null; if (member.Type == typeof(Decimal?)) { constant = Expression.Convert(Expression.Constant(Decimal.Parse(filter.Value)) , member.Type); } else if (member.Type == typeof(DateTime?)) { constant = Expression.Convert(Expression.Constant(DateTime.Parse(filter.Value)), member.Type); } else { constant = Expression.Convert(Expression.Constant(filter.Value), member.Type); } switch (filter.Operator) { case FilterOperator.Equals: return Expression.Equal(member, constant); case FilterOperator.GreaterThan: return Expression.GreaterThan(member, constant); case FilterOperator.GreaterThanOrEqual: return Expression.GreaterThanOrEqual(member, constant); case FilterOperator.LessThan: return Expression.LessThan(member, constant); case FilterOperator.LessThanOrEqual: return Expression.LessThanOrEqual(member, constant); case FilterOperator.Contains: return Expression.Call(member, containsMethod, constant); case FilterOperator.StartsWith: return Expression.Call(member, startsWithMethod, constant); case FilterOperator.EndsWith: return Expression.Call(member, endsWithMethod, constant); case FilterOperator.NotEqual: return Expression.Negate(Expression.Equal(member, constant)); } return null; } private static BinaryExpression GetExpression<T> (ParameterExpression param, FilterObject filter1, FilterObject filter2) { Expression bin1 = GetExpression<T>(param, filter1); Expression bin2 = GetExpression<T>(param, filter2); return Expression.AndAlso(bin1, bin2); } }
public class PagingInfo { public List<int> PageOptions { get; set; } public bool ShowPageOptions { get; set; } public int TotalItems { get; set; } public int ItemsPerPage { get; set; } public int CurrentPage { get; set; } public int TotalPages { get { return (int)Math.Ceiling((decimal)TotalItems / (ItemsPerPage != 0 ? ItemsPerPage : 1)); } } public SortObject Sort { get; set; } public IList<FilterObject> Filters { get; set; } public string SearchTerm { get; set; } } public class SortObject { public String SortColumn { get; set; } public SortDirection Direction { get; set; } } public class FilterObject { public string Column { get; set; } public string Value { get; set; } public FilterOperator Operator { get; set; } public FilterConjunction Conjunction { get; set; } } /********* ENUMS *************/ public enum SortDirection { NotSet, Ascending, Descending } public enum FilterOperator { Contains, GreaterThan, GreaterThanOrEqual, LessThan, LessThanOrEqual, StartsWith, EndsWith, Equals, NotEqual } public enum FilterConjunction { And, Or } public class Extensions { public static string GetWhereClause(FilterObject filterObj, Type valueType) { string whereClause = "true"; if (valueType != typeof (DateTime)) { switch (filterObj.Operator) { case FilterOperator.Contains: if (valueType == typeof (string)) whereClause += string.Format(" {0} {1}.Contains(\"{2}\")", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.GreaterThan: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1} > {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.GreaterThanOrEqual: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1} >= {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.LessThan: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1} < {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.LessThanOrEqual: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1} <= {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.StartsWith: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1}.StartsWith(\"{2}\")", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.EndsWith: if (valueType != typeof (string)) whereClause += string.Format(" {0} {1}.EndsWith(\"{2}\")", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.Equals: whereClause += string.Format(valueType == typeof (string) ? " {0} {1} == \"{2}\"" : " {0} {1} == {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; case FilterOperator.NotEqual: whereClause += string.Format(valueType == typeof (string) ? " {0} {1} != \"{2}\"" : " {0} {1} != {2}", filterObj.Conjunction, filterObj.Column, filterObj.Value); break; default: throw new ArgumentOutOfRangeException(); } } else { DateTime dt; DateTime.TryParse(filterObj.Value, out dt); switch (filterObj.Operator) { case FilterOperator.Contains: break; case FilterOperator.GreaterThan: whereClause += string.Format(" {0} {1} > DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; case FilterOperator.GreaterThanOrEqual: whereClause += string.Format(" {0} {1} >= DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; case FilterOperator.LessThan: whereClause += string.Format(" {0} {1} < DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; case FilterOperator.LessThanOrEqual: whereClause += string.Format(" {0} {1} <= DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; case FilterOperator.StartsWith: break; case FilterOperator.EndsWith: break; case FilterOperator.Equals: whereClause += string.Format(" {0} {1} == DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; case FilterOperator.NotEqual: whereClause += string.Format(" {0} {1} != DateTime(\"{2}\")", filterObj.Conjunction, filterObj.Column, dt); break; default: throw new ArgumentOutOfRangeException(); } } return whereClause; } }
MyDbContext.CS code:
public class GridViewModelProvider { internal static CustomersViewModel GetCustomersViewModel(MyDbContext db, PagingInfo PagingData) { int TotalItems = 0; var model = new CustomersViewModel() { Customers = GetResources(db.Customers.AsQueryable(), PagingData, out TotalItems), PagingInfo = new PagingInfo() { CurrentPage = PagingData.CurrentPage, ItemsPerPage = PagingData.ItemsPerPage, PageOptions = new List<int>() { 10, 25, 50, 100 }, ShowPageOptions = true, SearchTerm = PagingData.SearchTerm, Sort = PagingData.Sort, Filters = PagingData.Filters } }; model.PagingInfo.TotalItems = TotalItems; model.JsonPagingInfo = Json.Encode(model.PagingInfo); return model; } private static IQueryable<Customer> GetResources(IQueryable<Customer> Customers, PagingInfo PagingData, out int TotalItems) { var customers = Customers; //search if (!string.IsNullOrEmpty(PagingData.SearchTerm)) { customers = customers.Where(x => (x.CompanyName.Contains(PagingData.SearchTerm) || x.ContactTitle.Contains(PagingData.SearchTerm))); } //filter if (PagingData.Filters != null) { foreach (var filterObj in PagingData.Filters) { switch (filterObj.Column) { case "City": if (filterObj.Value.ToLower() != "all") customers = customers.Where(Extensions.GetWhereClause(filterObj, typeof(string))); break; //Add Other Filter Columns Here } } } TotalItems = customers.Count(); //sort customers = customers.OrderBy(x => x.Id); if (PagingData.Sort != null) { switch (PagingData.Sort.Direction) { case SortDirection.Ascending: if (PagingData.Sort.SortColumn == "CompanyName") { customers = customers.OrderBy(x => x.CompanyName); } else if (PagingData.Sort.SortColumn == "ContactTitle") { customers = customers.OrderBy(x => x.ContactTitle); } break; case SortDirection.Descending: if (PagingData.Sort.SortColumn == "CompanyName") { customers = customers.OrderByDescending(x => x.CompanyName); } else if (PagingData.Sort.SortColumn == "ContactTitle") { customers = customers.OrderByDescending(x => x.ContactTitle); } break; case SortDirection.NotSet: default: break; } } customers = customers .Skip((PagingData.CurrentPage - 1) * PagingData.ItemsPerPage).Take(PagingData.ItemsPerPage); return customers; } }
HomeController.cs controller:
/// <summary> /// 启用查询谓词的高效,动态组合。 /// </summary> public static class PredicateBuilder { /// <summary> /// 创建一个计算结果为true的谓词。 /// </summary> public static Expression<Func<T, bool>> True<T>() { return param => true; } /// <summary> /// 创建一个计算结果为false的谓词 /// </summary> public static Expression<Func<T, bool>> False<T>() { return param => false; } /// <summary> /// 创建一个从指定的lambda表达式的谓词表达式。 /// </summary> public static Expression<Func<T, bool>> Create<T>(Expression<Func<T, bool>> predicate) { return predicate; } /// <summary> /// 结合了第二第一谓词使用逻辑“and”。 /// </summary> public static Expression<Func<T, bool>> And<T>(this Expression<Func<T, bool>> first, Expression<Func<T, bool>> second) { return first.Compose(second, Expression.AndAlso); } /// <summary> /// 结合了第二第一谓词使用逻辑“or”。 /// </summary> public static Expression<Func<T, bool>> Or<T>(this Expression<Func<T, bool>> first, Expression<Func<T, bool>> second) { return first.Compose(second, Expression.OrElse); } /// <summary> ///否定谓词 /// </summary> public static Expression<Func<T, bool>> Not<T>(this Expression<Func<T, bool>> expression) { var negated = Expression.Not(expression.Body); return Expression.Lambda<Func<T, bool>>(negated, expression.Parameters); } /// <summary> /// 使用指定的合并函数,合并第二和第一表达式 /// </summary> static Expression<T> Compose<T>(this Expression<T> first, Expression<T> second, Func<Expression, Expression, Expression> merge) { //第二参数映射到第一参数 var map = first.Parameters .Select((f, i) => new { f, s = second.Parameters[i] }) .ToDictionary(p => p.s, p => p.f); //第一lambda表达式的参数替换在第二lambda表达式参数 var secondBody = ParameterRebinder.ReplaceParameters(map, second.Body); //从第一个表达式创建一个带参数的合并lambda表达式 return Expression.Lambda<T>(merge(first.Body, secondBody), first.Parameters); } class ParameterRebinder : ExpressionVisitor { readonly Dictionary<ParameterExpression, ParameterExpression> map; ParameterRebinder(Dictionary<ParameterExpression, ParameterExpression> map) { this.map = map ?? new Dictionary<ParameterExpression, ParameterExpression>(); } public static Expression ReplaceParameters(Dictionary<ParameterExpression, ParameterExpression> map, Expression exp) { return new ParameterRebinder(map).Visit(exp); } protected override Expression VisitParameter(ParameterExpression p) { ParameterExpression replacement; if (map.TryGetValue(p, out replacement)) { p = replacement; } return base.VisitParameter(p); } } }
Under the Home view folder:
_CustomersPart ial.cshtml
public class MyDbContext : DbContext { public MyDbContext() : base("DefaultConnection") { } public DbSet<Customer> Customers { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity<Customer>().Property(c => c.CompanyName).HasMaxLength(40); modelBuilder.Entity<Customer>().Property(c => c.ContactTitle).HasMaxLength(40); } }
_GridViewPartial. cshtml
public class HomeController : Controller { public ActionResult Index() { var model = new CustomersViewModel() { Customers = null, PagingInfo = new PagingInfo() { CurrentPage=1, ItemsPerPage= 10, PageOptions = new List<int>() { 10,25, 50, 100}, ShowPageOptions= true, TotalItems=1 } }; return View(model); } public ActionResult GetCustomers(PagingInfo PagingData) { var db = new MyDbContext(); var model = GridViewModelProvider.GetCustomersViewModel(db, PagingData); return PartialView("_CustomersPartial", model); } public ActionResult About() { ViewBag.Message = "您的应用程序描述页面。"; return View(); } public ActionResult Contact() { ViewBag.Message = "您的联系页面。"; return View(); } }
About.cshtml
@model mesoft.gridview.Models.CustomersViewModel @*在这里写下返回的数据的详细信息*@ <span class="gridview-data-details" style="display:none;">@Html.Raw(Model.JsonPagingInfo)</span> <table class="table table-bordered table-striped"> <thead> <tr class="gridview-list-header"> <th> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().Id)) </th> <th class="sortable" data-sort="CompanyName"> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().CompanyName)) </th> <th class="sortable" data-sort="ContactTitle"> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().ContactTitle)) </th> <th> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().Country)) </th> <th> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().City)) </th> <th> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().Address)) </th> <th> @(Html.DisplayNameFor(x => x.Customers.FirstOrDefault().Phone)) </th> <th> @Html.DisplayNameFor(x=> x.Customers.FirstOrDefault().Founded) </th> </tr> </thead> <tbody id="CustomersTable" class="gridview-list-items"> @if (Model.Customers.Any()) { foreach (var c in Model.Customers) { <tr> <td class="value">@c.Id</td> <td class="value">@c.CompanyName</td> <td class="value">@c.ContactTitle</td> <td class="value">@c.Country</td> <td class="value">@c.City</td> <td class="Description">@c.Address</td> <td class="value">@c.Phone</td> <td>@c.Founded</td> </tr> } } else { <tr> <td colspan="8"> <div class="alert alert-warning alert-dismissable"> <button type="button" class="close" data-dismiss="alert" aria-hidden="true">×</button> <strong>警告!</strong> 没有客户找到! </div> </td> </tr> } @Html.Raw(ViewBag.Script) </tbody> </table>
Contact.cshtml
@model mesoft.gridview.Models.CustomersViewModel <!-- GRIDVIEW--> <div class="gridview gridview1"> <!-- GridView Header--> <div class="gridview-header"> <!--GridView的头的左边部分--> <div class="col-sm-6"> <div class="gridview-search"> <div class="search input-group"> <input class="form-control" placeholder="Search" type="search"> <span class="input-group-btn"> <button class="btn btn-default" type="button"> <span class="fa fa-search"></span> <span class="sr-only">Search</span> </button> </span> </div> </div> </div> <!-- GridView的头右边部分--> <div class="col-sm-6 text-right"> <!-- 这里添加任何筛选操作--> @{ string[] cityFilters = {"Istanbul", "Trabzon", "Ankara", "Izmir", "Samsun", "Erzurum"}; } 根据城市筛选: <div class="btn-group"> <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown"> Select City <span class="caret"></span> </button> <ul class="dropdown-menu filter-parent" role="menu"> @foreach (var city in cityFilters) { <li><a href="#" class="filter" data-filter-column="City" data-filter-value="@city" data-filter-operator="@mesoft.gridview.Models.FilterOperator.Equals" data-filter-conjunction="@mesoft.gridview.Models.FilterConjunction.And">@city</a></li> } <li class="divider"></li> <li class="active"><a href="#" class="filter" data-filter-column="City" data-filter-value="All">All</a></li> </ul> </div> </div> </div> <!-- GridView ViewPort--> <div class="gridview-viewport" id="viewport" data-getdata-function="@Url.Action("GetCustomers", "Home")" data-default-pagesize="10"> <div class="gridview-canvas" style="min-height:400px;"> @*Data Will Load Here*@ </div> <div class="loading gridview gridview-loader"> <img src="~/content/images/loading.gif" /> </div> </div> <!-- GridView的分页区域--> <div class="gridview-footer"> @Html.DisplayFor(x => x.PagingInfo, "Pager") </div> </div>
Index.cshtml
@{ ViewBag.Title = "About"; } <h2>@ViewBag.Title.</h2> <h3>@ViewBag.Message</h3> <p>#</p>
Under the Shared folder:
_Layout.cshtml
@{ ViewBag.Title = "Contact"; } <h2>@ViewBag.Title.</h2> <h3>@ViewBag.Message</h3> <address> <strong>Support:</strong> <a href="827937686@qq.com">827937686@qq.com</a><br /> </address>
The running result is as shown in the figure:

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