Procedura: Associare dati al controllo MaskedTextBox

Articolo
12/18/2024

È possibile associare dati a un controllo MaskedTextBox così come è possibile per qualsiasi altro controllo Windows Form. Tuttavia, se il formato dei dati nel database non corrisponde al formato previsto dalla definizione della maschera, sarà necessario riformattare i dati. La procedura seguente illustra come eseguire questa operazione usando gli eventi Format e Parse della classe Binding per visualizzare campi di database di estensione telefono e numero di telefono separati come un singolo campo modificabile.

La procedura seguente richiede l'accesso a un database di SQL Server con il database di esempio Northwind installato.

Per associare dati a un controllo MaskedTextBox

Creare un nuovo progetto Windows Form.
Trascina due controlli TextBox sul tuo modulo; chiamali FirstName e LastName.
Trascina un controllo MaskedTextBox sul tuo modulo; chiamalo PhoneMask.
Impostare la proprietà Mask di PhoneMask su (000) 000-0000 x9999.

Aggiungere al modulo le seguenti importazioni di namespace.

using System.Data.SqlClient;

Imports System.Data.SqlClient

Fare clic con il pulsante destro del mouse sul modulo e scegliere Visualizza codice. Inserire questo codice in qualsiasi punto della classe del modulo.

Binding currentBinding, phoneBinding;  
DataSet employeesTable = new DataSet();  
SqlConnection sc;  
SqlDataAdapter dataConnect;  

private void Form1_Load(object sender, EventArgs e)  
{  
    DoMaskBinding();  
}  

private void DoMaskBinding()  
{  
    try  
    {  
        sc = new SqlConnection("Data Source=CLIENTUE;Initial Catalog=NORTHWIND;Integrated Security=SSPI");  
        sc.Open();  
    }  
    catch (Exception ex)  
    {  
        MessageBox.Show(ex.Message);  
        return;  
    }  

    dataConnect = new SqlDataAdapter("SELECT * FROM Employees", sc);  
    dataConnect.Fill(employeesTable, "Employees");  

    // Now bind MaskedTextBox to appropriate field. Note that we must create the Binding objects  
    // before adding them to the control - otherwise, we won't get a Format event on the
    // initial load.
    try  
    {  
        currentBinding = new Binding("Text", employeesTable, "Employees.FirstName");  
        firstName.DataBindings.Add(currentBinding);  

        currentBinding = new Binding("Text", employeesTable, "Employees.LastName");  
        lastName.DataBindings.Add(currentBinding);  

        phoneBinding =new Binding("Text", employeesTable, "Employees.HomePhone");  
        // We must add the event handlers before we bind, or the Format event will not get called  
        // for the first record.  
        phoneBinding.Format += new ConvertEventHandler(phoneBinding_Format);  
        phoneBinding.Parse += new ConvertEventHandler(phoneBinding_Parse);  
        phoneMask.DataBindings.Add(phoneBinding);  
    }  
    catch (Exception ex)  
    {  
        MessageBox.Show(ex.Message);  
        return;  
    }  
}

Dim WithEvents CurrentBinding, PhoneBinding As Binding  
Dim EmployeesTable As New DataSet()  
Dim sc As SqlConnection  
Dim DataConnect As SqlDataAdapter  

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load  
    DoMaskedBinding()  
End Sub  

Private Sub DoMaskedBinding()  
    Try  
        sc = New SqlConnection("Data Source=SERVERNAME;Initial Catalog=NORTHWIND;Integrated Security=SSPI")  
        sc.Open()  
    Catch ex As Exception  
        MessageBox.Show(ex.Message)  
        Exit Sub  
    End Try  

    DataConnect = New SqlDataAdapter("SELECT * FROM Employees", sc)  
    DataConnect.Fill(EmployeesTable, "Employees")  

    ' Now bind MaskedTextBox to appropriate field. Note that we must create the Binding objects  
    ' before adding them to the control - otherwise, we won't get a Format event on the
    ' initial load.  
    Try  
        CurrentBinding = New Binding("Text", EmployeesTable, "Employees.FirstName")  
        firstName.DataBindings.Add(CurrentBinding)  
        CurrentBinding = New Binding("Text", EmployeesTable, "Employees.LastName")  
        lastName.DataBindings.Add(CurrentBinding)  
        PhoneBinding = New Binding("Text", EmployeesTable, "Employees.HomePhone")  
        PhoneMask.DataBindings.Add(PhoneBinding)  
    Catch ex As Exception  
        MessageBox.Show(ex.Message)  
        Application.Exit()  
    End Try  
End Sub

Aggiungere gestori di eventi per gli eventi Format e Parse per combinare e separare i campi PhoneNumber e Extension dal DataSetassociato.

private void phoneBinding_Format(Object sender, ConvertEventArgs e)  
{  
    String ext;  

    DataRowView currentRow = (DataRowView)BindingContext[employeesTable, "Employees"].Current;  
    if (currentRow["Extension"] == null)
    {  
        ext = "";  
    } else
    {  
        ext = currentRow["Extension"].ToString();  
    }  

    e.Value = e.Value.ToString().Trim() + " x" + ext;  
}  

private void phoneBinding_Parse(Object sender, ConvertEventArgs e)  
{  
    String phoneNumberAndExt = e.Value.ToString();  

    int extIndex = phoneNumberAndExt.IndexOf("x");  
    String ext = phoneNumberAndExt.Substring(extIndex).Trim();  
    String phoneNumber = phoneNumberAndExt.Substring(0, extIndex).Trim();  

    //Get the current binding object, and set the new extension manually.
    DataRowView currentRow = (DataRowView)BindingContext[employeesTable, "Employees"].Current;  
    // Remove the "x" from the extension.  
    currentRow["Extension"] = ext.Substring(1);  

    //Return the phone number.  
    e.Value = phoneNumber;  
}

Private Sub PhoneBinding_Format(ByVal sender As Object, ByVal e As ConvertEventArgs) Handles PhoneBinding.Format  
    Dim Ext As String  

    Dim CurrentRow As DataRowView = CType(Me.BindingContext(EmployeesTable, "Employees").Current, DataRowView)  
    If (CurrentRow("Extension") Is Nothing) Then  
        Ext = ""  
    Else  
        Ext = CurrentRow("Extension").ToString()  
    End If  

    e.Value = e.Value.ToString().Trim() & " x" & Ext  
End Sub  

Private Sub PhoneBinding_Parse(ByVal sender As Object, ByVal e As ConvertEventArgs) Handles PhoneBinding.Parse  
    Dim PhoneNumberAndExt As String = e.Value.ToString()  

    Dim ExtIndex As Integer = PhoneNumberAndExt.IndexOf("x")  
    Dim Ext As String = PhoneNumberAndExt.Substring(ExtIndex).Trim()  
    Dim PhoneNumber As String = PhoneNumberAndExt.Substring(0, ExtIndex).Trim()  

    ' Get the current binding object, and set the new extension manually.
    Dim CurrentRow As DataRowView = CType(Me.BindingContext(EmployeesTable, "Employees").Current, DataRowView)  
    ' Remove the "x" from the extension.  
    CurrentRow("Extension") = CObj(Ext.Substring(1))  

    ' Return the phone number.  
    e.Value = PhoneNumber  
End Sub

Aggiungi due controlli Button al modulo. Denominarli previousButton e nextButton. Fare doppio clic su ogni pulsante per aggiungere un gestore eventi Click e compilare i gestori eventi, come illustrato nell'esempio di codice seguente.

private void previousButton_Click(object sender, EventArgs e)  
{  
    BindingContext[employeesTable, "Employees"].Position = BindingContext[employeesTable, "Employees"].Position - 1;  
}  

private void nextButton_Click(object sender, EventArgs e)  
{  
    BindingContext[employeesTable, "Employees"].Position = BindingContext[employeesTable, "Employees"].Position + 1;  
}

Private Sub PreviousButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PreviousButton.Click  
    Me.BindingContext(EmployeesTable, "Employees").Position = Me.BindingContext(EmployeesTable, "Employees").Position - 1  
End Sub  

Private Sub NextButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NextButton.Click  
    Me.BindingContext(EmployeesTable, "Employees").Position = Me.BindingContext(EmployeesTable, "Employees").Position + 1  
End Sub

Esegui l'esempio. Modificare i dati e usare i pulsanti Indietro e Avanti per verificare che i dati siano salvati correttamente nella DataSet.

Esempio

L'esempio di codice seguente è il listato di codice completo risultante dal completamento della procedura precedente.

#pragma region Using directives

#using <System.dll>
#using <System.Data.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>
#using <System.Xml.dll>
#using <System.EnterpriseServices.dll>
#using <System.Transactions.dll>

using namespace System;
using namespace System::Collections::Generic;
using namespace System::ComponentModel;
using namespace System::Data;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Data::SqlClient;

#pragma endregion

namespace MaskedTextBoxDataCSharp
{
    public ref class Form1 : public Form
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
    private:
        System::ComponentModel::IContainer^ components;

    public:
        Form1()
        {
            InitializeComponent();
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
    protected:
        ~Form1()
        {
            if (components != nullptr)
            {
                delete components;
            }
        }



#pragma region Windows Form Designer generated code

               /// <summary>
               /// Required method for Designer support - do not modify
               /// the contents of this method with the code editor.
               /// </summary>
    private:
        void InitializeComponent()
        {
            employeesTable = gcnew DataSet();
            components = nullptr;
            this->firstName = gcnew System::Windows::Forms::TextBox();
            this->lastName = gcnew System::Windows::Forms::TextBox();
            this->phoneMask = gcnew System::Windows::Forms::MaskedTextBox();
            this->previousButton = gcnew System::Windows::Forms::Button();
            this->nextButton = gcnew System::Windows::Forms::Button();
            this->SuspendLayout();
            //
            // firstName
            //
            this->firstName->Location = System::Drawing::Point(13, 14);
            this->firstName->Name = "firstName";
            this->firstName->Size = System::Drawing::Size(184, 20);
            this->firstName->TabIndex = 0;
            //
            // lastName
            //
            this->lastName->Location = System::Drawing::Point(204, 14);
            this->lastName->Name = "lastName";
            this->lastName->Size = System::Drawing::Size(184, 20);
            this->lastName->TabIndex = 1;
            //
            // phoneMask
            //
            this->phoneMask->Location = System::Drawing::Point(441, 14);
            this->phoneMask->Mask = "(009) 000-0000 x9999";
            this->phoneMask->Name = "phoneMask";
            this->phoneMask->Size = System::Drawing::Size(169, 20);
            this->phoneMask->TabIndex = 2;
            //
            // previousButton
            //
            this->previousButton->Location = System::Drawing::Point(630, 14);
            this->previousButton->Name = "previousButton";
            this->previousButton->TabIndex = 3;
            this->previousButton->Text = "Previous";
            this->previousButton->Click += gcnew System::EventHandler(this,&Form1::previousButton_Click);
            //
            // nextButton
            //
            this->nextButton->Location = System::Drawing::Point(723, 14);
            this->nextButton->Name = "nextButton";
            this->nextButton->TabIndex = 4;
            this->nextButton->Text = "Next";
            this->nextButton->Click += gcnew System::EventHandler(this,&Form1::nextButton_Click);
            //
            // Form1
            //
            this->AutoScaleBaseSize = System::Drawing::Size(5, 13);
            this->ClientSize = System::Drawing::Size(887, 46);
            this->Controls->Add(this->nextButton);
            this->Controls->Add(this->previousButton);
            this->Controls->Add(this->phoneMask);
            this->Controls->Add(this->lastName);
            this->Controls->Add(this->firstName);
            this->Name = "Form1";
            this->Text = "Form1";
            this->Load += gcnew System::EventHandler(this,&Form1::Form1_Load);
            this->ResumeLayout(false);
            this->PerformLayout();
        }

#pragma endregion

    private:
        System::Windows::Forms::TextBox^ firstName;
        System::Windows::Forms::TextBox^ lastName;
        System::Windows::Forms::MaskedTextBox^ phoneMask;
        System::Windows::Forms::Button^ previousButton;
        System::Windows::Forms::Button^ nextButton;

    private:
        Binding^ currentBinding;
        Binding^ phoneBinding;
        DataSet^ employeesTable;
        SqlConnection^ sc;
        SqlDataAdapter^ dataConnect;

    private:
        void Form1_Load(Object^ sender, EventArgs^ e)
        {
            DoMaskBinding();
        }

    private:
        void DoMaskBinding()
        {
            try
            {
                sc = gcnew SqlConnection("Data Source=localhost;" +
                    "Initial Catalog=NORTHWIND;Integrated Security=SSPI");
                sc->Open();
            }
            catch (Exception^ ex)
            {
                MessageBox::Show(ex->Message);
                return;
            }

            dataConnect = gcnew SqlDataAdapter("SELECT * FROM Employees", sc);
            dataConnect->Fill(employeesTable, "Employees");


            // Now bind MaskedTextBox to appropriate field. Note that we must
            // create the Binding objects before adding them to the control -
            // otherwise, we won't get a Format event on the initial load.
            try
            {
                currentBinding = gcnew Binding("Text", employeesTable,
                    "Employees.FirstName");
                firstName->DataBindings->Add(currentBinding);

                currentBinding = gcnew Binding("Text", employeesTable,
                    "Employees.LastName");
                lastName->DataBindings->Add(currentBinding);

                phoneBinding = gcnew Binding("Text", employeesTable, 
                    "Employees.HomePhone");
                // We must add the event handlers before we bind, or the
                // Format event will not get called for the first record.
                phoneBinding->Format += gcnew
                    ConvertEventHandler(this, &Form1::phoneBinding_Format);
                phoneBinding->Parse += gcnew
                    ConvertEventHandler(this, &Form1::phoneBinding_Parse);
                phoneMask->DataBindings->Add(phoneBinding);
            }
            catch (Exception^ ex)
            {
                MessageBox::Show(ex->Message);
                return;
            }
        }

    private:
        void phoneBinding_Format(Object^ sender, ConvertEventArgs^ e)
        {
            String^ ext;

            DataRowView^ currentRow = (DataRowView^) BindingContext[
                employeesTable, "Employees"]->Current;
                if (currentRow["Extension"] == nullptr)
                {
                    ext = "";
                }
                else
                {
                    ext = currentRow["Extension"]->ToString();
                }

                e->Value = e->Value->ToString()->Trim() + " x" + ext;
        }

    private:
        void phoneBinding_Parse(Object^ sender, ConvertEventArgs^ e)
        {
            String^ phoneNumberAndExt = e->Value->ToString();

            int extIndex = phoneNumberAndExt->IndexOf("x");
            String^ ext = phoneNumberAndExt->Substring(extIndex)->Trim();
            String^ phoneNumber = 
                phoneNumberAndExt->Substring(0, extIndex)->Trim();

            //Get the current binding object, and set the new extension 
            //manually.
            DataRowView^ currentRow = 
                (DataRowView^ ) BindingContext[employeesTable,
                "Employees"]->Current;
            // Remove the "x" from the extension.
            currentRow["Extension"] = ext->Substring(1);

            //Return the phone number.
            e->Value = phoneNumber;
        }

    private:
        void previousButton_Click(Object^ sender, EventArgs^ e)
        {
            BindingContext[employeesTable, "Employees"]->Position =
                BindingContext[employeesTable, "Employees"]->Position - 1;
        }

    private:
        void nextButton_Click(Object^ sender, EventArgs^ e)
        {
            BindingContext[employeesTable, "Employees"]->Position =
                BindingContext[employeesTable, "Employees"]->Position + 1;
        }
    };
}

[STAThread]
int main()
{
    Application::EnableVisualStyles();
    Application::Run(gcnew MaskedTextBoxDataCSharp::Form1());
}

#region Using directives

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Windows.Forms;
using System.Data.SqlClient;

#endregion

namespace MaskedTextBoxDataCSharp
{
    partial class Form1 : Form
    {
        Binding currentBinding, phoneBinding;
        DataSet employeesTable = new DataSet();
        SqlConnection sc;
        SqlDataAdapter dataConnect;

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            DoMaskBinding();
        }

        private void DoMaskBinding()
        {
            try
            {
                sc = new SqlConnection("Data Source=localhost;Initial Catalog=NORTHWIND;Integrated Security=SSPI");
                sc.Open();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return;
            }

            dataConnect = new SqlDataAdapter("SELECT * FROM Employees", sc);
            dataConnect.Fill(employeesTable, "Employees");

            // Now bind MaskedTextBox to appropriate field. Note that we must create the Binding objects
            // before adding them to the control - otherwise, we won't get a Format event on the
            // initial load.
            try
            {
                currentBinding = new Binding("Text", employeesTable, "Employees.FirstName");
                firstName.DataBindings.Add(currentBinding);

                currentBinding = new Binding("Text", employeesTable, "Employees.LastName");
                lastName.DataBindings.Add(currentBinding);

                phoneBinding =new Binding("Text", employeesTable, "Employees.HomePhone");
                // We must add the event handlers before we bind, or the Format event will not get called
                // for the first record.
                phoneBinding.Format += new ConvertEventHandler(phoneBinding_Format);
                phoneBinding.Parse += new ConvertEventHandler(phoneBinding_Parse);
                phoneMask.DataBindings.Add(phoneBinding);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return;
            }
        }

        private void phoneBinding_Format(Object sender, ConvertEventArgs e)
        {
            String ext;

            DataRowView currentRow = (DataRowView)BindingContext[employeesTable, "Employees"].Current;
            if (currentRow["Extension"] == null)
            {
                ext = "";
            } else
            {
                ext = currentRow["Extension"].ToString();
            }

            e.Value = e.Value.ToString().Trim() + " x" + ext;
        }

        private void phoneBinding_Parse(Object sender, ConvertEventArgs e)
        {
            String phoneNumberAndExt = e.Value.ToString();

            int extIndex = phoneNumberAndExt.IndexOf("x");
            String ext = phoneNumberAndExt.Substring(extIndex).Trim();
            String phoneNumber = phoneNumberAndExt.Substring(0, extIndex).Trim();

            //Get the current binding object, and set the new extension manually.
            DataRowView currentRow = (DataRowView)BindingContext[employeesTable, "Employees"].Current;
            // Remove the "x" from the extension.
            currentRow["Extension"] = ext.Substring(1);

            //Return the phone number.
            e.Value = phoneNumber;
        }

        private void previousButton_Click(object sender, EventArgs e)
        {
            BindingContext[employeesTable, "Employees"].Position = BindingContext[employeesTable, "Employees"].Position - 1;
        }

        private void nextButton_Click(object sender, EventArgs e)
        {
            BindingContext[employeesTable, "Employees"].Position = BindingContext[employeesTable, "Employees"].Position + 1;
        }
    }
}

Imports System.Data.SqlClient

Public Class Form1
    Dim WithEvents CurrentBinding, PhoneBinding As Binding
    Dim EmployeesTable As New DataSet()
    Dim sc As SqlConnection
    Dim DataConnect As SqlDataAdapter

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        DoMaskedBinding()
    End Sub

    Private Sub DoMaskedBinding()
        Try
            sc = New SqlConnection("Data Source=localhost;Initial Catalog=NORTHWIND;Integrated Security=SSPI")
            sc.Open()
        Catch ex As Exception
            MessageBox.Show(ex.Message)
            Application.Exit()
        End Try

        DataConnect = New SqlDataAdapter("SELECT * FROM Employees", sc)
        DataConnect.Fill(EmployeesTable, "Employees")

        ' Now bind MaskedTextBox to appropriate field. Note that we must create the Binding objects
        ' before adding them to the control - otherwise, we won't get a Format event on the 
        ' initial load. 
        Try
            CurrentBinding = New Binding("Text", EmployeesTable, "Employees.FirstName")
            firstName.DataBindings.Add(CurrentBinding)
            CurrentBinding = New Binding("Text", EmployeesTable, "Employees.LastName")
            lastName.DataBindings.Add(CurrentBinding)
            PhoneBinding = New Binding("Text", EmployeesTable, "Employees.HomePhone")
            PhoneMask.DataBindings.Add(PhoneBinding)
        Catch ex As Exception
            MessageBox.Show(ex.Message)
            Application.Exit()
        End Try
    End Sub

    Private Sub PhoneBinding_Format(ByVal sender As Object, ByVal e As ConvertEventArgs) Handles PhoneBinding.Format
        Dim Ext As String

        Dim CurrentRow As DataRowView = CType(Me.BindingContext(EmployeesTable, "Employees").Current, DataRowView)
        If (CurrentRow("Extension") Is Nothing) Then
            Ext = ""
        Else
            Ext = CurrentRow("Extension").ToString()
        End If

        e.Value = e.Value.ToString().Trim() & " x" & Ext
    End Sub

    Private Sub PhoneBinding_Parse(ByVal sender As Object, ByVal e As ConvertEventArgs) Handles PhoneBinding.Parse
        Dim PhoneNumberAndExt As String = e.Value.ToString()

        Dim ExtIndex As Integer = PhoneNumberAndExt.IndexOf("x")
        Dim Ext As String = PhoneNumberAndExt.Substring(ExtIndex).Trim()
        Dim PhoneNumber As String = PhoneNumberAndExt.Substring(0, ExtIndex).Trim()

        ' Get the current binding object, and set the new extension manually. 
        Dim CurrentRow As DataRowView = CType(Me.BindingContext(EmployeesTable, "Employees").Current, DataRowView)
        ' Remove the "x" from the extension.
        CurrentRow("Extension") = CObj(Ext.Substring(1))

        ' Return the phone number.
        e.Value = PhoneNumber
    End Sub

    Private Sub NextButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NextButton.Click
        Me.BindingContext(EmployeesTable, "Employees").Position = Me.BindingContext(EmployeesTable, "Employees").Position + 1
    End Sub

    Private Sub PreviousButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PreviousButton.Click
        Me.BindingContext(EmployeesTable, "Employees").Position = Me.BindingContext(EmployeesTable, "Employees").Position - 1
    End Sub
End Class

Compilazione del codice

Creare un progetto Visual C# o Visual Basic.
Aggiungere i controlli TextBox e MaskedTextBox al modulo, come descritto nella procedura precedente.
Aprire il file di codice sorgente per il modulo predefinito del progetto.
Sostituire il codice sorgente in questo file con il codice elencato nella sezione precedente "Code".
Compilare l'applicazione.

Vedere anche

Guida: utilizzo del controllo MaskedTextBox

Condividi tramite

Procedura: Associare dati al controllo MaskedTextBox

Per associare dati a un controllo MaskedTextBox

Esempio

Compilazione del codice

Vedere anche

Risorse aggiuntive