public IQueryable <T> Filter <Key>(System.Linq.Expressions.Expression <Func <T, Key> > sortingSelector, System.Linq.Expressions.Expression <Func <T, bool> > filter, out int total, SortingOrders sortby = SortingOrders.Asc, int index = 0, int size = 50)
{
var entities = All();
var query = sortby == SortingOrders.Asc ? entities.OrderBy(sortingSelector.Compile()).Where(filter.Compile())
: entities.OrderByDescending(sortingSelector.Compile()).Where(filter.Compile());
total = query.Count();
var skipCount = index * size;
return(skipCount > 0 ? query.Skip(skipCount).Take(size).AsQueryable <T>() : query.Take(size).AsQueryable <T>());
}
public IEnumerable <T> WhereQ <T>(System.Linq.Expressions.Expression <System.Func <T, bool> > predicate) where T : IThing
{
if (typeof(T).GetInterface(typeof(ILink).FullName) != null)
{
return(edges.OfType <T>().Where(predicate.Compile()));
}
else
{
return(items.OfType <T>().Where(predicate.Compile()));
}
}
public override IList <TModelType> FindBy <TKey>(System.Linq.Expressions.Expression <Func <TModelType, bool> > query, System.Linq.Expressions.Expression <Func <TModelType, TKey> > order, int pageIndex, int pageCount, OrderType orderType, out int rowCount)
{
rowCount = this.Count(query);
if (orderType == OrderType.ASC || orderType == OrderType.Default)
{
return(this.tempContext.Persistence.Query(query.Compile()).OrderBy(order.Compile()).Skip((pageIndex - 1) * pageCount).Take(pageCount).ToList());
}
else
{
return(this.tempContext.Persistence.Query(query.Compile()).OrderByDescending(order.Compile()).Skip((pageIndex - 1) * pageCount).Take(pageCount).ToList());
}
}
private void TitleContext_OnClickEvent(System.Linq.Expressions.Expression <Func <TModel, object> > valueExpression)
{
if (orderType == OrderType.None || orderType == OrderType.Descending)
{
Items = Items.OrderBy(valueExpression.Compile()).ToList();
orderType = OrderType.Ascending;
}
else
{
Items = Items.OrderByDescending(valueExpression.Compile()).ToList();
orderType = OrderType.Descending;
}
StateHasChanged();
}
public override void Delete(System.Linq.Expressions.Expression <Func <T, bool> > filter)
{
foreach (T item in CurrentList.Where(filter.Compile()))
{
CurrentList.Remove(item);
}
}
// i => i < 5;
static void Example1()
{
// <Snippet1>
// Lambda expression as executable code.
Func <int, bool> deleg = i => i < 5;
// Invoke the delegate and display the output.
Console.WriteLine("deleg(4) = {0}", deleg(4));
// Lambda expression as data in the form of an expression tree.
System.Linq.Expressions.Expression <Func <int, bool> > expr = i => i < 5;
// Compile the expression tree into executable code.
Func <int, bool> deleg2 = expr.Compile();
// Invoke the method and print the output.
Console.WriteLine("deleg2(4) = {0}", deleg2(4));
/* This code produces the following output:
*
* deleg(4) = True
* deleg2(4) = True
*/
// </Snippet1>
}
/// <summary>
/// 重写获取分页数据方法
/// </summary>
/// <param name="totalCount">总记录数</param>
/// <param name="errorMsg">异常信息</param>
/// <param name="permissionValidate">是否过滤权限</param>
/// <param name="pageIndex">页号</param>
/// <param name="pageSize">每页记录数</param>
/// <param name="orderFields">排序字段</param>
/// <param name="isDescs">是否降序</param>
/// <param name="expression">条件表达式</param>
/// <param name="whereSql">where语句</param>
/// <param name="references">是否加载导航属性</param>
/// <param name="connString">数据库连接字符串</param>
/// <returns></returns>
public override List <Sys_DbConfig> GetPageEntities(out long totalCount, out string errorMsg, bool permissionValidate = true, int pageIndex = 1, int pageSize = 10, List <string> orderFields = null, List <bool> isDescs = null, System.Linq.Expressions.Expression <Func <Sys_DbConfig, bool> > expression = null, string whereSql = null, List <string> fieldNames = null, bool references = false, string connString = null)
{
totalCount = 0;
BaseDAL <Sys_Module> moduleDal = new BaseDAL <Sys_Module>(this.CurrUser);
int dataSourceType = (int)ModuleDataSourceType.DbTable;
List <Sys_Module> modules = expression == null?moduleDal.GetPageEntities(out totalCount, out errorMsg, false, pageIndex, pageSize, null, null, x => x.DataSourceType == dataSourceType) : moduleDal.GetEntities(out errorMsg, x => x.DataSourceType == dataSourceType, null, false);
List <Sys_DbConfig> list = modules.Select(x => GetModuleCacheConfig(x.TableName, x.Name, x.Id)).ToList();
list = list.Where(x => x != null).ToList();
//将未添加到模块表中的模块也加进来
List <Type> modelTypes = GetAllModelTypes();
if (modelTypes == null || modelTypes.Count == 0)
{
return(new List <Sys_DbConfig>());
}
List <string> tables = moduleDal.GetEntities(out errorMsg, x => x.TableName != null && x.TableName != string.Empty).Select(x => x.TableName).ToList();
list.AddRange(modelTypes.Where(x => !tables.Contains(x.Name)).Select(x => GetModuleCacheConfig(x.Name)));
if (expression != null)
{
list = list.Where(expression.Compile()).ToList();
totalCount = list.Count;
}
//页序号
int index = pageIndex < 1 ? 0 : (pageIndex - 1);
//每页记录数
int rows = pageSize < 1 ? 10 : (pageSize > 2000 ? 2000 : pageSize);
list = list.Skip <Sys_DbConfig>(rows * index).Take <Sys_DbConfig>(rows).OrderByDescending(x => x.CurrPageDensity).ToList();
return(list);
}
public IEnumerable <TEntity> GetByPredicate(System.Linq.Expressions.Expression <Func <TEntity, bool> > f)
{
Func <TEntity, bool> func = f.Compile();
IEnumerable <TEntity> answers = GetAll();
return(answers.Where(answ => func(answ)));
}
public void GetCurrentClassLoggerLambdaTest()
{
System.Linq.Expressions.Expression <Func <ILogger> > sum = () => LogManager.GetCurrentClassLogger();
ILogger logger = sum.Compile().Invoke();
Assert.Equal("NLog.UnitTests.GetLoggerTests", logger.Name);
}
/// <summary>
/// 获取实体集合重写
/// </summary>
/// <param name="errorMsg"></param>
/// <param name="expression"></param>
/// <param name="whereSql"></param>
/// <param name="permissionFilter"></param>
/// <param name="orderFields"></param>
/// <param name="isDescs"></param>
/// <param name="top"></param>
/// <param name="references"></param>
/// <param name="connString"></param>
/// <returns></returns>
public override List <Sys_CacheConfig> GetEntities(out string errorMsg, System.Linq.Expressions.Expression <Func <Sys_CacheConfig, bool> > expression = null, string whereSql = null, bool permissionFilter = true, List <string> orderFields = null, List <bool> isDescs = null, int?top = null, List <string> fieldNames = null, bool references = false, string connString = null)
{
BaseDAL <Sys_Module> moduleDal = new BaseDAL <Sys_Module>(this.CurrUser);
int dataSourceType = (int)ModuleDataSourceType.DbTable;
List <Sys_Module> modules = moduleDal.GetEntities(out errorMsg, x => x.DataSourceType == dataSourceType, null, permissionFilter);
List <Sys_CacheConfig> list = modules.Select(x => GetModuleCacheConfig(x.TableName, x.Name, x.Id)).ToList();
//将未添加到模块表中的模块也加进来
List <Type> modelTypes = GetAllModelTypes();
List <string> tables = moduleDal.GetEntities(out errorMsg, x => x.TableName != null && x.TableName != string.Empty).Select(x => x.TableName).ToList();
list.AddRange(modelTypes.Where(x => !tables.Contains(x.Name)).Select(x => GetModuleCacheConfig(x.Name)));
if (expression != null)
{
list = list.Where(expression.Compile()).ToList();
if (orderFields != null && orderFields.Count > 0)
{
for (int i = 0; i < orderFields.Count; i++)
{
string orderField = string.IsNullOrEmpty(orderFields[i]) ? "Id" : orderFields[i];
bool isdesc = isDescs != null && orderFields.Count == isDescs.Count ? isDescs[i] : true;
SortComparer <Sys_CacheConfig> reverser = new SortComparer <Sys_CacheConfig>(typeof(Sys_CacheConfig), orderField, isdesc ? ReverserInfo.Direction.DESC : ReverserInfo.Direction.ASC);
list.Sort(reverser);
}
}
}
return(list);
}
public Func <object, object> GetFunc(
Type instanceType,
string memberName)
{
System.Reflection.PropertyInfo member = instanceType.GetProperty(
memberName,
System.Reflection.BindingFlags.Public |
System.Reflection.BindingFlags.Instance);
System.Linq.Expressions.ParameterExpression instance =
System.Linq.Expressions.Expression.Parameter(typeof(object), "i");
System.Linq.Expressions.MemberExpression memberExp =
System.Linq.Expressions.Expression.Property(
System.Linq.Expressions.Expression.Convert(instance, member.DeclaringType),
member);
System.Linq.Expressions.Expression <Func <object, object> > getter =
System.Linq.Expressions.Expression.Lambda <Func <object, object> >(
System.Linq.Expressions.Expression.Convert(memberExp, typeof(object)),
instance);
Func <object, object> func = getter.Compile();
return(func);
}
public void ComparePerformanceOfExpressionCompileVersusCreateMetaClosure()
{
int xx = 2;
System.Linq.Expressions.Expression <Func <int, int, int> > multiplierByClosureConstantExpression = (y, z) => xx * (y + z);
DateTime start;
TimeSpan duration;
start = DateTime.Now;
for (int i = 0; i < 100000; i++)
{
multiplierByClosureConstantExpression.Compile();
}
duration = DateTime.Now - start;
Console.WriteLine(duration);
Func <int, int, int, int> multiplierByClosureConstant = (x, y, z) => x * (y + z);
start = DateTime.Now;
for (int i = 0; i < 100000; i++)
{
List <object> constants = new List <object>()
{
2
};
Func <int, int, int> curriedFunction = ClosedToOpenExpressionFactory.CreateMetaClosure <Func <int, int, int> >(
multiplierByClosureConstant,
constants);
}
duration = DateTime.Now - start;
Console.WriteLine(duration);
}
private IAccessorLambda InvokeAccessor(System.Linq.Expressions.Expression <Func <IAccessorLambda, IAccessorLambda> > invokeExpression)
{
accessors.All(o => { invokeExpression.Compile()(o); return(true); });
//return this.typeLambda;
return(this);
}
internal void AddCompilerError(Cursor cursor, System.Linq.Expressions.Expression <Func <string> > error, params object[] args)
{
var parts = ((System.Linq.Expressions.MemberExpression)error.Body).Member.Name.Split('_');
var errorId = parts[0];
bool?isWarning = null;
switch (parts[1])
{
case "ERROR":
isWarning = false;
break;
case "WARNING":
isWarning = true;
break;
#if DEBUG
default:
throw new ArgumentException(string.Format(CultureInfo.CurrentCulture, "Unknown error type '{0}'.", parts[1]), "error");
#endif
}
var errorFormat = error.Compile()();
var errorText = string.Format(CultureInfo.CurrentCulture, errorFormat, args);
this.Errors.Add(new CompilerError(cursor.FileName ?? string.Empty, cursor.Line, cursor.Column, errorId, errorText)
{
IsWarning = isWarning ?? true
});
}
/// <summary>
/// Recupera a propriedade do filho compilada.
/// </summary>
/// <returns></returns>
private Func <TLinkDataModel, int> GetChildPropertyCompiled()
{
if (_childProperty != null && _childPropertyCompiled == null)
{
_childPropertyCompiled = _childProperty.Compile();
}
return(_childPropertyCompiled);
}
/// <summary>
/// Recupera a propriedade do filho compilada.
/// </summary>
/// <returns></returns>
private Func <TLinkDataModel, int?> GetChildPropertyNullableCompiled()
{
if (_childPropertyNullable != null && _childPropertyNullableCompiled == null)
{
_childPropertyNullableCompiled = _childPropertyNullable.Compile();
}
return(_childPropertyNullableCompiled);
}
/// <summary>
/// Recupera o delegate usado para recupera o identificador unico do pai.
/// </summary>
/// <param name="parentPropertyUid"></param>
/// <returns></returns>
private static Func <Colosoft.Data.IModel, int> GetParentUidGetter(System.Linq.Expressions.Expression <Func <TParentModel, int> > parentPropertyUid)
{
var getter = parentPropertyUid.Compile();
return(parent => {
return getter((TParentModel)parent);
});
}
public BlogTemplate GetBy(System.Linq.Expressions.Expression <Func <BlogTemplate, bool> > predicate, params System.Linq.Expressions.Expression <Func <BlogTemplate, object> >[] includes)
{
if (includes != null && includes.Any())
{
return(_baseRepo.GetBy(predicate, includes));
}
return(_cache.CachedBlogTemplates.SingleOrDefault(predicate.Compile()));
}
/// <summary>
/// Recupera a propriedade estrangeira compilada.
/// </summary>
/// <returns></returns>
private Func <TLinkParentDataModel, int?> GetForeignPropertyNullableCompiled()
{
if (_foreignPropertyNullable != null && _foreignPropertyNullableCompiled == null)
{
_foreignPropertyNullableCompiled = _foreignPropertyNullable.Compile();
}
return(_foreignPropertyNullableCompiled);
}
static void Main(string[] args)
{
//Console.WriteLine("Hello World!");
System.Linq.Expressions.Expression <Func <int, int> > e = x => x * x;
var a = e.Compile();
Console.WriteLine(a(7));
}
static void Main(string[] args)
{
System.Linq.Expressions.Expression <Func <int, int> > expressionTree = x => x * x;
Console.WriteLine("Expression Tree:");
Console.WriteLine(expressionTree);
var a = expressionTree.Compile();
Console.WriteLine("Result: " + a(8));
}
public void Register <K>(System.Linq.Expressions.Expression <Func <object, K> > msgCreationFunction)
where K : IActorMessage
{
var func = msgCreationFunction.Compile();
var invoker = new ActorMessageInvocation <K>(func);
var msgType = LocalSwitchboard.HandleValueTypeMessage(typeof(K));
_msgTypeToInstatiation.TryAdd(msgType, invoker);
}
static void Main(string[] args)
{
Func <int, int> square = (x) => { return(x * x); };
System.Linq.Expressions.Expression <Func <int, int> > e = x => x * x;
var a = e.Compile();
Console.WriteLine(a(7));
}
public void ExpressionTrees()
{
System.Linq.Expressions.Expression <Converter <int, double> > converter = x => Math.Pow(x, 0.5);
// representing code as data
Console.WriteLine(converter);
Converter <int, double> compiles = converter.Compile();
}
/// <summary>
/// Renders the boolean attribute, specified by the <paramref name="attributeName"/>, as long as the value of <paramref name="expression"/> evaluates to true.
/// </summary>
/// <typeparam name="TModel"></typeparam>
/// <param name="htmlHelper"></param>
/// <param name="attributeName"></param>
/// <param name="expression"></param>
/// <returns></returns>
public static IHtmlContent RenderAttributeFor <TModel>(this Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper <TModel> htmlHelper, String attributeName, System.Linq.Expressions.Expression <Func <TModel, bool> > expression)
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression));
}
bool shouldEmit = expression.Compile( ).Invoke(htmlHelper.ViewData.Model);
return(htmlHelper.RenderAttribute(attributeName, shouldEmit));
}
public IQueryable <IEntry> GetFilteredEntries(System.Linq.Expressions.Expression <Func <IEntry, bool> > filter, bool includeDeleted = false)
{
var filterDelegate = filter.Compile();
var allResultsDb = includeDeleted ? _context.Get <WP8Entry>("select * from WP8Entry").ToList() : _context.Get <WP8Entry>("select* from WP8Entry where IsDeleted = 0").ToList();
var allResults = allResultsDb.Select(it => it.AsIEntry()).ToList();
var results = allResults.Where(it => filterDelegate(it)).ToList();
return(results.AsQueryable());
}
/// <summary>
/// Example: using (Utils.SetUnsetMagic(() => obj.SomeProperty, "temp disable")) { DoSomething(); }
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="variable"></param>
/// <param name="value"></param>
/// <returns></returns>
public static Undoer.UndoOnDispose SetUnsetMagic <T>(System.Linq.Expressions.Expression <Func <T> > variable, T value)
{
var oldValue = variable.Compile()();
var parameterExpression = System.Linq.Expressions.Expression.Parameter(typeof(T));
var assignExpr = System.Linq.Expressions.Expression.Assign(variable.Body, parameterExpression);
var setter = System.Linq.Expressions.Expression.Lambda <Action <T> >(assignExpr, parameterExpression).Compile();
return(new Undoer(() => setter(value), () => setter(oldValue)).Do());
}
public IList <TEntity> GetAllBySort(System.Linq.Expressions.Expression <Func <TEntity, bool> > predicate, int page, int pageSize, string sortItem, int sortType)
{
BsonDocument sort = new BsonDocument {
{ sortItem, sortType }
};
var result = _collection.Find(new BsonDocument()).Limit(pageSize).Sort(sort).ToListAsync().Result;
return(result.AsQueryable().Where(predicate.Compile()).ToList());
}
public IQueryable <IEntry> GetFilteredEntries(System.Linq.Expressions.Expression <Func <IEntry, bool> > filter, bool includeDeleted = false)
{
lock (_lock)
{
var filterDelegate = filter.Compile();
var allResults = _context.Entries.Select(it => (IEntry)it).ToList();
var results = allResults.Where(it => includeDeleted ? filterDelegate(it) : filterDelegate(it) && (!it.IsDeleted.HasValue || (it.IsDeleted.HasValue && !it.IsDeleted.Value))).ToList();
return(results.AsQueryable());
}
}
public Task <List <T> > WhereAsync(System.Linq.Expressions.Expression <Func <T, bool> > predicate)
{
if (!_Initialised)
{
NotInitialisedError();
}
var result = _Table.Where(predicate.Compile()).ToList();
return(Task.FromResult(result));
}