Ejercicio
Tareas de ejercicio
Objetivo
Crea un programa en Visual Basic que puede almacenar hasta 2000 "tareas pendientes". Para cada tarea, debe conservar los siguientes datos:
• Fecha (un conjunto de 3 datos: día, mes y año)
• Descripción de la tarea
• Nivel de importancia (1 a 10)
• Categoría
El programa debe permitir al usuario las siguientes operaciones:
1 - Añadir una nueva tarea (la fecha debe "parecer correcta": día 1 al 31, mes 1 al 12, año entre 1000 y 3000).
2 - Mostrar las tareas entre dos fechas determinadas (día, mes y año). Si el usuario presiona Intro sin especificar la fecha, se tomará como "hoy". Debe mostrar el número de cada registro, la fecha (DD / MM / AAAA), descripción, categoría e importancia, todo en la misma línea, separado con guiones.
3 - Encuentre tareas que contengan un texto determinado (en descripción o categoría, no distingue entre mayúsculas y minúsculas). Mostrará número, fecha y descripción (solo 50 letras, en caso de que fuera más largo). Se debe notificar al usuario si no se encuentra ninguno.
4 - Actualizar un registro (te pedirá el número, mostrará el valor anterior de cada campo y el usuario podrá pulsar Intro para no modificar ninguno de los datos). Se debe advertir al usuario (pero no se le debe preguntar de nuevo) si ingresa un número de registro incorrecto. No es necesario validar ninguno de los campos.
5 - Eliminar algunos datos, entre dos posiciones indicadas por el usuario. Se debe advertir al usuario (pero no se le debe preguntar de nuevo) si ingresa algún número de registro incorrecto. Cada registro que se elimine debe mostrarse y se debe solicitar al usuario confirmación.
6 - Ordenar los datos alfabéticamente por fecha y (si dos fechas son iguales) por descripción.
7 - Buscar duplicados: Si dos registros tienen la misma descripción, ambos se mostrarán en pantalla.
P - Salir (finalizar la aplicación; como no almacenamos la información, se perderá).
(Sugerencia: puede conocer la fecha actual usando DateTime.Now.Day, DateTime.Now.Month y DateTime.Now.Year).
Código
Imports System
Public Class exercis95
Structure DateType
Public year As UShort
Public month As Byte
Public day As Byte
End Structure
Structure TaskType
Public date As DateType
Public description As String
Public level As Byte
Public category As String
End Structure
Public Shared Sub Main()
Dim capacity As Integer = 2000
Dim tasks As TaskType() = New TaskType(capacity - 1) {}
Dim [option] As Char
Dim counter As Integer = 0
Dim search, newValue As String
Dim found As Boolean
Do
Console.WriteLine()
Console.WriteLine("Tasks database")
Console.WriteLine()
Console.WriteLine("1- Add a new task.")
Console.WriteLine("2- Show the tasks between two certain dates.")
Console.WriteLine("3- Find tasks that contain a certain text.")
Console.WriteLine("4- Update a record.")
Console.WriteLine("5- Delete some data, between two positions indicated.")
Console.WriteLine("6- Sort the data alphabetically by date.")
Console.WriteLine("7- Find Duplicates.")
Console.WriteLine("Q- Quit.")
Console.WriteLine("Enter an option:")
[option] = Convert.ToChar(Console.ReadLine().ToUpper())
Select Case [option]
Case "1"c
If counter < capacity Then
Console.Write("Enter the Description of the task: ")
tasks(counter).description = Console.ReadLine()
Console.Write("Enter the Level of the task (1-10): ")
tasks(counter).level = Convert.ToByte(Console.ReadLine())
Console.Write("Enter the Category of the task: ")
tasks(counter).category = Console.ReadLine()
Do
Console.Write("Enter the Day of the task (1 to 31): ")
tasks(counter).date.day = Convert.ToByte(Console.ReadLine())
If tasks(counter).date.day < 1 OrElse tasks(counter).date.day > 31 Then Console.WriteLine("Not a valid day!")
Loop While tasks(counter).date.day < 1 OrElse tasks(counter).date.day > 31
Do
Console.Write("Enter the Month of the task (1 to 12): ")
tasks(counter).date.month = Convert.ToByte(Console.ReadLine())
If tasks(counter).date.month < 1 OrElse tasks(counter).date.month > 12 Then Console.WriteLine("Not a valid month!")
Loop While tasks(counter).date.month < 1 OrElse tasks(counter).date.month > 12
Do
Console.Write("Enter the Year of the task: ")
tasks(counter).date.year = Convert.ToUInt16(Console.ReadLine())
If tasks(counter).date.year < 1000 OrElse tasks(counter).date.year > 3000 Then Console.WriteLine("Not a valid year!")
Loop While tasks(counter).date.year < 1000 OrElse tasks(counter).date.year > 3000
counter += 1
Else
Console.WriteLine("Database full.")
End If
Case "2"c
If counter >= 1 Then
Dim startDay, startMonth As Byte
Dim startYear As UShort
Dim endDay, endMonth As Byte
Dim endYear As UShort
Console.WriteLine("Starting day: ")
Dim number As String = Console.ReadLine()
If number = "" Then
startDay = Convert.ToByte(DateTime.Now.Day)
Else
startDay = Convert.ToByte(number)
End If
Console.WriteLine("Starting month: ")
number = Console.ReadLine()
If number = "" Then
startMonth = Convert.ToByte(DateTime.Now.Month)
Else
startMonth = Convert.ToByte(number)
End If
Console.WriteLine("Starting year: ")
number = Console.ReadLine()
If number = "" Then
startYear = Convert.ToUInt16(DateTime.Now.Year)
Else
startYear = Convert.ToUInt16(number)
End If
Console.WriteLine("Final day: ")
number = Console.ReadLine()
If number = "" Then
endDay = Convert.ToByte(DateTime.Now.Day)
Else
endDay = Convert.ToByte(number)
End If
Console.WriteLine("Final month: ")
number = Console.ReadLine()
If number = "" Then
endMonth = Convert.ToByte(DateTime.Now.Month)
Else
endMonth = Convert.ToByte(number)
End If
Console.WriteLine("Final year: ")
number = Console.ReadLine()
If number = "" Then
endYear = Convert.ToUInt16(DateTime.Now.Year)
Else
endYear = Convert.ToUInt16(number)
End If
Dim startDate As String = "" & startYear & startMonth.ToString("00") & startDay.ToString("00")
Dim endDate As String = "" & endYear & endMonth.ToString("00") & endDay.ToString("00")
For i As Integer = 0 To counter - 1
Dim currentDate As String = "" & tasks(i).date.year & tasks(i).date.month.ToString("00") & tasks(i).date.day.ToString("00")
If currentDate.CompareTo(startDate) >= 0 AndAlso currentDate.CompareTo(endDate) <= 0 Then
Console.WriteLine("The number is {0}: {1}/{2}/" & "{3} - {4} - {5} - {6}.", i + 1, tasks(i).date.day, tasks(i).date.month, tasks(i).date.year, tasks(i).description, tasks(i).category, tasks(i).level)
End If
Next
Else
Console.WriteLine("Database empty.")
End If
Case "3"c
If counter >= 1 Then
Console.Write("Enter the text to search: ")
search = Console.ReadLine()
found = False
Dim newValue5 As String
For i As Integer = 0 To counter - 1
If tasks(i).description.IndexOf(search) >= 0 OrElse tasks(i).category.IndexOf(search) >= 0 Then
If tasks(i).description.Length > 50 Then
newValue5 = tasks(i).description.Substring(0, 50)
Else
newValue5 = tasks(i).description
End If
found = True
Console.WriteLine("{0}: {1}/{2}/{3} - {4}", i + 1, tasks(i).date.day, tasks(i).date.month, tasks(i).date.year, newValue5)
End If
Next
If Not found Then Console.WriteLine("Not found.")
Else
Console.WriteLine("Database empty.")
End If
Case "4"c
If counter >= 1 Then
Console.Write("Enter the number of the task to update: ")
Dim update As Integer = Convert.ToInt32(Console.ReadLine()) - 1
If (update >= 0) AndAlso (update < counter) Then
Console.Write("Description ({0}): ", tasks(update).description)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).description = newValue
Console.WriteLine("Level ({0}): ", tasks(update).level)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).level = Convert.ToByte(newValue)
Console.WriteLine("Category ({0}): ", tasks(update).category)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).category = newValue
Console.WriteLine("Year ({0}): ", tasks(update).date.year)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).date.year = Convert.ToUInt16(newValue)
Console.WriteLine("Month ({0}): ", tasks(update).date.month)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).date.month = Convert.ToByte(newValue)
Console.WriteLine("Day ({0}): ", tasks(update).date.day)
newValue = Console.ReadLine()
If newValue <> "" Then tasks(update).date.day = Convert.ToByte(newValue)
Else
Console.WriteLine("Wrong number entered.")
End If
Else
Console.WriteLine("Database empty.")
End If
Case "5"c
If counter >= 1 Then
Console.Write("Enter the first number of data to delete: ")
Dim delete As Integer = Convert.ToInt32(Console.ReadLine()) - 1
Console.Write("Enter the second number of data to delete: ")
Dim delete2 As Integer = Convert.ToInt32(Console.ReadLine()) - 1
For pos As Integer = delete To delete2
For i As Integer = delete To counter - 1
tasks(i) = tasks(i + 1)
Next
counter -= 1
Next
Else
Console.WriteLine("Database empty.")
End If
Case "6"c
For i As Integer = 0 To counter - 1 - 1
Dim firstDate As String = "" & tasks(i).date.year & tasks(i).date.month.ToString("00") & tasks(i).date.day.ToString("00") & tasks(i).description
For j As Integer = i + 1 To counter - 1
Dim secondDate As String = "" & tasks(j).date.year & tasks(j).date.month.ToString("00") & tasks(j).date.day.ToString("00") & tasks(j).description
If firstDate.CompareTo(secondDate) > 0 Then
Dim aux As TaskType = tasks(i)
tasks(i) = tasks(j)
tasks(j) = aux
End If
Next
Next
Case "7"c
For i As Integer = 0 To counter - 1 - 1
For j As Integer = i + 1 To counter - 1
If tasks(i).description = tasks(j).description Then
Console.WriteLine("{0} - {1}/{2}/{3}", tasks(i).description, tasks(i).date.day, tasks(i).date.month, tasks(i).date.year)
Console.WriteLine("{0} - {1}/{2}/{3}", tasks(j).description, tasks(j).date.day, tasks(j).date.month, tasks(j).date.year)
End If
Next
Next
Case "Q"c
Console.WriteLine("Quitting...")
Case Else
Console.WriteLine("You entered a wrong option. Please re-enter it.")
End Select
Loop While [option] <> "Q"c
End Sub
End Class