Cora SeQuence supports several LINQ extension methods, which perform transformations on IEnumberable types (standard .NET functionality). The standard query operators allow queries to be applied to any IEnumerable<T>-based information source.
In the table below, seq is an IEnumberable<T> instance, predicate is a boolean expression, and selector is an expression of any type.
| Method Type | Purpose | Example | Return Value Type |
|---|---|---|---|
| Where(predicate) | Gets the items that meet the condition. | {Task1}.Tasks.Where(IsCompleted) | IEnumerable |
| Last() | Gets the last element. | Wf.ActivityScope(“taskb”).Last() | Element |
| seq.LastOrDefault() | Gets the last element or returns the default type in case there are no activities. In case of class, it is null. In case of int, it is zero. | Wf.ActivityScope(“taskb”).LastOrDefault() | Element or Null |
| Last(predicate) | Gets the last element that meets the condition. | Wf.ActivityScope(“taskb”).Last(UpdatedAt < now() ) | Element |
| seq.LastOrDefault(predicate) | Gets the last element that meets the condition, or the default type. In case of class it is null. In case of int, it is zero. | Wf.ActivityScope(“taskb”).LastOrDefault(UpdatedAt < now() ) | Element or Null |
| First() | Gets the first element. | {Task1}.Tasks.Where(IsCompleted).First() | Element |
| FirstOrDefault() | Gets the first element or the default type in case there are no activities. In case of class, it is null. In case of int, it is zero. | {Task1}.Tasks.Where(IsCompleted).FirstOrDefault() | Element or Null |
| At(int index) | Gets the element at a specific index. | {Task1}.Tasks.At(1) | Element |
| ElementAt(int index) | Same as At(). | {Task1}.Tasks.ElementAt(1) | Element |
| Count(predicate) | Counts the elements that meet the conditions. | {Form1}.Query(“DataTable1”).Count(Field("Price")>100) | Integer |
| Count() | Counts the elements. | {Task1}.Tasks.Count() | Integer |
| All(predicate) | Returns true if all elements meet the condition, otherwise it returns false. | {Form1}.Query(“DataTable1”).All(Field("Checked")==True) | Boolean |
| Any() | Returns true if there are any elements, otherwise it returns false. | {Form1}.Query(“DataTable1”).Any() | Boolean |
| Any(predicate) | Returns true if there are any elements that meet the condition, otherwise it returns false. | {Form1}.Query(“DataTable1”).Any( Field("Checked")==True) | Boolean |
| OrderBy(selector) | Sorts elements in ascending order. | {Form1}.Query("DataTable1").OrderBy(Field("txtName")) | Elements |
| seq.OrderByDescending(selector) | Sorts elements in descending order. | {Form1}.Query("DataTable1").OrderByDescending(Field("txt1")) | Elements |
| Reverse() | Inverts the order of the elements in a sequence. | {Form1}.Query("DataTable1").Select(Field("txtName")).Reverse() | Elements |
| Distinct() | Returns distinct elements from a sequence. | {Form1}.Query("DataTable1").Select(Field("txtName")).Distinct() | Distinct elements from a sequence |
| Take(int count) | Returns a specified number of contiguous elements from the start of a sequence. | {Form1}.Query(“DataTable1”).Take(1).Select(Field(“txt1”)) | Elements |
| seq.TakeWhile(predicate) | Returns elements from a sequence as long as a specified condition is true, and then skips the remaining elements. | {Form1}.Query(“DataTable1”).TakeWhile(Field(“Status”==True).Select(Field(“txt1”)) | Elements |
| Select(selector) | Selects an element. | {Form1}.Query(“DefaultView”).Select(Field(“txt1”)) | Elements |
| seq.SelectMany(selector) | Selects many elements. | Gets all tasks from all instances. {Task1}.Scope().SelectMany(tasks) Gets all user IDs that have not taken action on the tasks. {Task1}.Scope().SelectMany(Tasks).where(not isCompleted).Select(ToID) | Elements |
| Skip(int count) | Bypasses the first specified number (in the example, two elements) of elements in a sequence, and then returns the remaining elements | {Form1}.Query(“DataTable1”).Skip(2).Select(Field(“txt1”)) | Elements |
| seq.SkipWhile(predicate) | Bypasses elements in a sequence as long as they meet the specified condition and they are located at the beginning of the items list. After this, the remaining elements are returned. | {Form1}.Query(“DataTable1”).SkipWhile(Field(“cmb1.value” == 0).Select(Field(“txt1”)) | Elements |
| Min(selector) | Returns the element with the minimum value. | {form1}.Query(“DataTable1”).Min(field("FieldNum")) | Element |
| Max(selector) | Returns the maximum value from all values of a specified field. | {form1}.Query(“DataTable1”).Max(field("FieldNum")) To return the whole row: {form1}.Query(“DataTable1”).OrderByDescending(Field(“FieldNum”)).First() | Element |
| ToArray() | Converts the elements to an array. | {form01}.Query(“DataTable1”).Row().field(“Items”).ToArray() | Array |
