<<назад StudentsController2.vb (Contoso University).
1: '#Const Type = "DirectScaffold"
2: 'or --------------------
3: '#Const Type1 = "ScaffoldedIndex"
4: '#Const Type1 = "SortOnly"
5: '#Const Type1 = "SortFilter"
6: #Const Type1 = "SortFilterPage"
7: '#Const Type1 = "DynamicLinq"
8: '--------------------------
9: '#Const Type2 = "ReadFirst"
10: #Const Type2 = "CreateAndAttach"
11: '--------------------------
12: #Const Type3 = "DeleteWithReadFirst"
13: '#Const Type3 = "DeleteWithoutReadFirst"
14:
15: Imports System
16: Imports System.Collections.Generic
17: Imports System.Data
18: Imports System.Data.Entity
19: Imports System.Linq
20: Imports System.Threading.Tasks
21: Imports System.Net
22: Imports System.Web
23: Imports System.Web.Mvc
24: Imports CU_VB_3
25: Imports CU_VB_3.Models
26: Imports System.Data.Entity.Infrastructure
27: Imports System.IdentityModel.Metadata
28: Imports System.Collections.ObjectModel
29:
30: Namespace Controllers
31: Public Class StudentsController
32: Inherits System.Web.Mvc.Controller
33:
34: #If Type = "DirectScaffold" Then
35: #Region "DirectScaffold"
36: Private db As New SchoolContext
37:
38: ' GET: Students
39: Async Function Index() As Task(Of ActionResult)
40: Return View(Await Task.FromResult(db.Students.ToList()))
41: End Function
42:
43: ' GET: Students/Details/5
44: Async Function Details(ByVal id As Integer?) As Task(Of ActionResult)
45: If IsNothing(id) Then
46: Return New HttpStatusCodeResult(HttpStatusCode.BadRequest)
47: End If
48: Dim student As Student = Await db.People.FindAsync(id)
49: If IsNothing(student) Then
50: Return HttpNotFound()
51: End If
52: Return View(student)
53: End Function
54:
55: ' GET: Students/Create
56: Function Create() As ActionResult
57: Return View()
58: End Function
59:
60: ' POST: Students/Create
61: 'To protect from overposting attacks, please enable the specific properties you want to bind to, for
62: 'more details see https://go.microsoft.com/fwlink/?LinkId=317598.
63: <HttpPost()>
64: <ValidateAntiForgeryToken()>
65: Async Function Create(<Bind(Include:="ID,LastName,FirstMidName,EnrollmentDate")> ByVal student As Student) As Task(Of ActionResult)
66: If ModelState.IsValid Then
67: db.People.Add(student)
68: Await db.SaveChangesAsync()
69: Return RedirectToAction("Index")
70: End If
71: Return View(student)
72: End Function
73:
74: ' GET: Students/Edit/5
75: Async Function Edit(ByVal id As Integer?) As Task(Of ActionResult)
76: If IsNothing(id) Then
77: Return New HttpStatusCodeResult(HttpStatusCode.BadRequest)
78: End If
79: Dim student As Student = Await db.People.FindAsync(id)
80: If IsNothing(student) Then
81: Return HttpNotFound()
82: End If
83: Return View(student)
84: End Function
85:
86: ' POST: Students/Edit/5
87: 'To protect from overposting attacks, please enable the specific properties you want to bind to, for
88: 'more details see https://go.microsoft.com/fwlink/?LinkId=317598.
89: <HttpPost()>
90: <ValidateAntiForgeryToken()>
91: Async Function Edit(<Bind(Include:="ID,LastName,FirstMidName,EnrollmentDate")> ByVal student As Student) As Task(Of ActionResult)
92: If ModelState.IsValid Then
93: db.Entry(student).State = EntityState.Modified
94: Await db.SaveChangesAsync()
95: Return RedirectToAction("Index")
96: End If
97: Return View(student)
98: End Function
99:
100: ' GET: Students/Delete/5
101: Async Function Delete(ByVal id As Integer?) As Task(Of ActionResult)
102: If IsNothing(id) Then
103: Return New HttpStatusCodeResult(HttpStatusCode.BadRequest)
104: End If
105: Dim student As Student = Await db.People.FindAsync(id)
106: If IsNothing(student) Then
107: Return HttpNotFound()
108: End If
109: Return View(student)
110: End Function
111:
112: ' POST: Students/Delete/5
113: <HttpPost()>
114: <ActionName("Delete")>
115: <ValidateAntiForgeryToken()>
116: Async Function DeleteConfirmed(ByVal id As Integer) As Task(Of ActionResult)
117: Dim student As Student = Await db.People.FindAsync(id)
118: db.People.Remove(student)
119: Await db.SaveChangesAsync()
120: Return RedirectToAction("Index")
121: End Function
122:
123: Protected Overrides Sub Dispose(ByVal disposing As Boolean)
124: If (disposing) Then
125: db.Dispose()
126: End If
127: MyBase.Dispose(disposing)
128: End Sub
129: #End Region
130: #End If
131: Private ReadOnly _context As SchoolContext
132: Public Sub New(ByVal context As SchoolContext)
133: _context = context
134: End Sub
135: Public Sub New()
136: _context = New SchoolContext
137: End Sub
138:
139: #If Type1 = "ScaffoldedIndex" Then
140:
141: Public Async Function Index() As Task(Of ActionResult)
142: Return View(Await _context.Students.ToListAsync())
143: End Function
144: #ElseIf Type1 = "SortOnly" Then
145:
146: Public Async Function Index(ByVal sortOrder As String) As Task(Of ActionResult)
147: ViewData("NameSortParm") = If(String.IsNullOrEmpty(sortOrder), "name_desc", "")
148: ViewData("DateSortParm") = If(sortOrder = "Date", "date_desc", "Date")
149: Dim students = From s In _context.Students Select s
150:
151: Select Case sortOrder
152: Case "name_desc"
153: students = students.OrderByDescending(Function(s) s.LastName)
154: Case "Date"
155: students = students.OrderBy(Function(s) s.EnrollmentDate)
156: Case "date_desc"
157: students = students.OrderByDescending(Function(s) s.EnrollmentDate)
158: Case Else
159: students = students.OrderBy(Function(s) s.LastName)
160: End Select
161:
162: Return View(Await students.AsNoTracking().ToListAsync())
163: End Function
164: #ElseIf Type1 = "SortFilter" Then
165:
166: Public Async Function Index(ByVal sortOrder As String, ByVal searchString As String) As Task(Of ActionResult)
167: ViewData("NameSortParm") = If(String.IsNullOrEmpty(sortOrder), "name_desc", "")
168: ViewData("DateSortParm") = If(sortOrder = "Date", "date_desc", "Date")
169: ViewData("CurrentFilter") = searchString
170: Dim students = From s In _context.Students Select s
171:
172: If Not String.IsNullOrEmpty(searchString) Then
173: students = students.Where(Function(s) s.LastName.Contains(searchString) OrElse s.FirstMidName.Contains(searchString))
174: End If
175:
176: Select Case sortOrder
177: Case "name_desc"
178: students = students.OrderByDescending(Function(s) s.LastName)
179: Case "Date"
180: students = students.OrderBy(Function(s) s.EnrollmentDate)
181: Case "date_desc"
182: students = students.OrderByDescending(Function(s) s.EnrollmentDate)
183: Case Else
184: students = students.OrderBy(Function(s) s.LastName)
185: End Select
186:
187: Return View(Await students.AsNoTracking().ToListAsync())
188: End Function
189: #ElseIf Type1 = "SortFilterPage" Then
190:
191: Public Async Function Index(ByVal sortOrder As String, ByVal currentFilter As String, ByVal searchString As String, ByVal page As Integer?) As Task(Of ActionResult)
192: ViewData("CurrentSort") = sortOrder
193: ViewData("NameSortParm") = If(String.IsNullOrEmpty(sortOrder), "name_desc", "")
194: ViewData("DateSortParm") = If(sortOrder = "Date", "date_desc", "Date")
195:
196: If searchString IsNot Nothing Then
197: page = 1
198: Else
199: searchString = currentFilter
200: End If
201:
202: ViewData("CurrentFilter") = searchString
203: Dim students = From s In _context.Students Select s
204:
205: If Not String.IsNullOrEmpty(searchString) Then
206: students = students.Where(Function(s) s.LastName.Contains(searchString) OrElse s.FirstMidName.Contains(searchString))
207: End If
208:
209: Select Case sortOrder
210: Case "name_desc"
211: students = students.OrderByDescending(Function(s) s.LastName)
212: Case "Date"
213: students = students.OrderBy(Function(s) s.EnrollmentDate)
214: Case "date_desc"
215: students = students.OrderByDescending(Function(s) s.EnrollmentDate)
216: Case Else
217: students = students.OrderBy(Function(s) s.LastName)
218: End Select
219:
220: Dim pageSize As Integer = 3
221: Return View(Await PaginatedList(Of Student).CreateAsync(students.AsNoTracking(), If(page, 1), pageSize))
222: End Function
223:
224: #ElseIf Type1 = "DynamicLinq" Then
225:
226: Public Async Function Index(ByVal sortOrder As String, ByVal currentFilter As String, ByVal searchString As String, ByVal page As Integer?) As Task(Of IActionResult)
227: ViewData("CurrentSort") = sortOrder
228: ViewData("NameSortParm") = If(String.IsNullOrEmpty(sortOrder), "LastName_desc", "")
229: ViewData("DateSortParm") = If(sortOrder = "EnrollmentDate", "EnrollmentDate_desc", "EnrollmentDate")
230:
231: If searchString IsNot Nothing Then
232: page = 1
233: Else
234: searchString = currentFilter
235: End If
236:
237: ViewData("CurrentFilter") = searchString
238: Dim students = From s In _context.Students Select s
239:
240: If Not String.IsNullOrEmpty(searchString) Then
241: students = students.Where(Function(s) s.LastName.Contains(searchString) OrElse s.FirstMidName.Contains(searchString))
242: End If
243:
244: If String.IsNullOrEmpty(sortOrder) Then
245: sortOrder = "LastName"
246: End If
247:
248: Dim descending As Boolean = False
249:
250: If sortOrder.EndsWith("_desc") Then
251: sortOrder = sortOrder.Substring(0, sortOrder.Length - 5)
252: descending = True
253: End If
254:
255: If descending Then
256: students = students.OrderByDescending(Function(e) EF.[Property](Of Object)(e, sortOrder))
257: Else
258: students = students.OrderBy(Function(e) EF.[Property](Of Object)(e, sortOrder))
259: End If
260:
261: Dim pageSize As Integer = 3
262: Return View(Await PaginatedList(Of Student).CreateAsync(students.AsNoTracking(), If(page, 1), pageSize))
263: End Function
264: #End If
265:
266: Public Async Function Details(ByVal id As Integer?) As Task(Of ActionResult)
267: If id Is Nothing Then
268: Return HttpNotFound()
269: End If
270:
271: Dim student = Await _context.Students.Include(Function(s) s.Enrollments).AsNoTracking().SingleOrDefaultAsync(Function(m) m.ID = id)
272: '.ThenInclude(Function(e) e.Course).AsNoTracking().SingleOrDefaultAsync(Function(m) m.ID = id)
273:
274: If student Is Nothing Then
275: Return HttpNotFound()t
276: End If
277:
278: Return View(student)
279: End Function
280:
281: Public Function Create() As ActionResult
282: Return View()
283: End Function
284:
285: <HttpPost>
286: <ValidateAntiForgeryToken>
287: Public Async Function Create(<Bind(Include:="EnrollmentDate,FirstMidName,LastName")> ByVal student As Student) As Task(Of ActionResult)
288: Try
289: If ModelState.IsValid Then
290: _context.Add(student)
291: Await _context.SaveChangesAsync()
292: Return RedirectToAction(NameOf(Index))
293: End If
294:
295: Catch __unusedDbUpdateException1__ As DbUpdateException
296: ModelState.AddModelError("", "Unable to save changes. " & "Try again, and if the problem persists " & "see your system administrator.")
297: End Try
298:
299: Return View(student)
300: End Function
301:
302: 'Edit Get
303: Public Async Function Edit(ByVal id As Integer?) As Task(Of ActionResult)
304: If id Is Nothing Then
305: Return HttpNotFound()
306: End If
307:
308: Dim student = Await _context.Students.AsNoTracking().SingleOrDefaultAsync(Function(m) m.ID = id)
309:
310: If student Is Nothing Then
311: Return HttpNotFound()
312: End If
313:
314: Return View(student)
315: End Function
316:
317: #If Type2 = "ReadFirst" Then
318:
319: <HttpPost, ActionName("Edit")>
320: <ValidateAntiForgeryToken>
321: Public Async Function EditPost(ByVal id As Integer?) As Task(Of ActionResult)
322: If id Is Nothing Then
323: Return HttpNotFound()
324: End If
325:
326: Dim studentToUpdate = Await _context.Students.SingleOrDefaultAsync(Function(s) s.ID = id)
327:
328: If Await TryUpdateModelAsync(Of Student)(studentToUpdate, "", Function(s) s.FirstMidName, Function(s) s.LastName, Function(s) s.EnrollmentDate) Then
329:
330: Try
331: Await _context.SaveChangesAsync()
332: Return RedirectToAction(NameOf(Index))
333: Catch __unusedDbUpdateException1__ As DbUpdateException
334: ModelState.AddModelError("", "Unable to save changes. " & "Try again, and if the problem persists, " & "see your system administrator.")
335: End Try
336: End If
337:
338: Return View(studentToUpdate)
339: End Function
340:
341: #ElseIf Type2 = "CreateAndAttach" Then
342:
343:
344:
345: <HttpPost, ActionName("Edit")>
346: <ValidateAntiForgeryToken>
347: Public Async Function Edit(ByVal id As Integer, <Bind(Include:="ID,EnrollmentDate,FirstMidName,LastName")> ByVal student As Student) As Task(Of ActionResult)
348: If id <> student.ID Then
349: Return HttpNotFound()
350: End If
351:
352: If ModelState.IsValid Then
353:
354: Try
355: _context.Update(student)
356: Await _context.SaveChangesAsync()
357: Return RedirectToAction(NameOf(Index))
358: Catch __unusedDbUpdateException1__ As DbUpdateException
359: ModelState.AddModelError("", "Unable to save changes. " & "Try again, and if the problem persists, " & "see your system administrator.")
360: End Try
361: End If
362:
363: Return View(student)
364: End Function
365: #End If
366:
367:
368: 'delete Get
369: Public Async Function Delete(ByVal id As Integer?, ByVal Optional saveChangesError As Boolean? = False) As Task(Of ActionResult)
370: If id Is Nothing Then
371: Return HttpNotFound()
372: End If
373:
374: Dim student = Await _context.Students.AsNoTracking().SingleOrDefaultAsync(Function(m) m.ID = id)
375:
376: If student Is Nothing Then
377: Return HttpNotFound()
378: End If
379:
380: If saveChangesError.GetValueOrDefault() Then
381: ViewData("ErrorMessage") = "Delete failed. Try again, and if the problem persists " & "see your system administrator."
382: End If
383:
384: Return View(student)
385: End Function
386:
387:
388: #If Type3 = "DeleteWithReadFirst" Then
389:
390: <HttpPost, ActionName("Delete")>
391: <ValidateAntiForgeryToken>
392: Public Async Function DeleteConfirmed(ByVal id As Integer) As Task(Of ActionResult)
393: Dim student = Await _context.Students.AsNoTracking().SingleOrDefaultAsync(Function(m) m.ID = id)
394:
395: If student Is Nothing Then
396: Return RedirectToAction(NameOf(Index))
397: End If
398:
399: Try
400: _context.Students.Remove(student)
401: Await _context.SaveChangesAsync()
402: Return RedirectToAction(NameOf(Index))
403: Catch __unusedDbUpdateException1__ As DbUpdateException
404: Return RedirectToAction(NameOf(Delete), New With {
405: .id = id,
406: .saveChangesError = True
407: })
408: End Try
409: End Function
410:
411: #ElseIf Type3 = "DeleteWithoutReadFirst" Then
412:
413: <HttpPost>
414: <ValidateAntiForgeryToken>
415: Public Async Function DeleteConfirmed(ByVal id As Integer) As Task(Of ActionResult)
416: Try
417: Dim studentToDelete As Student = New Student() With {
418: .ID = id
419: }
420: _context.Entry(studentToDelete).State = EntityState.Deleted
421: Await _context.SaveChangesAsync()
422: Return RedirectToAction(NameOf(Index))
423: Catch __unusedDbUpdateException1__ As DbUpdateException
424: Return RedirectToAction(NameOf(Delete), New With {
425: .id = id,
426: .saveChangesError = True
427: })
428: End Try
429:
430: End Function
431: #End If
432:
433: End Class
434: End Namespace
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