IndentedTextWriter Classe

Definição

public ref class IndentedTextWriter : System::IO::TextWriter

public class IndentedTextWriter : System.IO.TextWriter

type IndentedTextWriter = class
    inherit TextWriter

Public Class IndentedTextWriter
Inherits TextWriter

Herança

Object

MarshalByRefObject

TextWriter

IndentedTextWriter

Exemplos

O exemplo de código seguinte demonstra o uso de um IndentedTextWriter para escrever texto em diferentes níveis de indentação.

using System;
using System.CodeDom;
using System.CodeDom.Compiler;
using System.ComponentModel;
using System.IO;
using System.Windows.Forms;

namespace IndentedTextWriterExample
{
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.TextBox textBox1;

        private string CreateMultilevelIndentString()
        {
            // Creates a TextWriter to use as the base output writer.
            System.IO.StringWriter baseTextWriter = new System.IO.StringWriter();

            // Create an IndentedTextWriter and set the tab string to use
            // as the indentation string for each indentation level.
            System.CodeDom.Compiler.IndentedTextWriter indentWriter = new IndentedTextWriter(baseTextWriter, "    ");

            // Sets the indentation level.
            indentWriter.Indent = 0;

            // Output test strings at stepped indentations through a recursive loop method.
            WriteLevel(indentWriter, 0, 5);

            // Return the resulting string from the base StringWriter.
            return baseTextWriter.ToString();
        }

        private void WriteLevel(IndentedTextWriter indentWriter, int level, int totalLevels)
        {
            // Output a test string with a new-line character at the end.
            indentWriter.WriteLine("This is a test phrase. Current indentation level: "+level.ToString());

            // If not yet at the highest recursion level, call this output method for the next level of indentation.
            if( level < totalLevels )
            {
                // Increase the indentation count for the next level of indented output.
                indentWriter.Indent++;

                // Call the WriteLevel method to write test output for the next level of indentation.
                WriteLevel(indentWriter, level+1, totalLevels);

                // Restores the indentation count for this level after the recursive branch method has returned.
                indentWriter.Indent--;
            }
            else
            {
                // Outputs a string using the WriteLineNoTabs method.
                indentWriter.WriteLineNoTabs("This is a test phrase written with the IndentTextWriter.WriteLineNoTabs method.");
            }

            // Outputs a test string with a new-line character at the end.
            indentWriter.WriteLine("This is a test phrase. Current indentation level: "+level.ToString());
        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            textBox1.Text = CreateMultilevelIndentString();
        }

        public Form1()
        {
            System.Windows.Forms.Button button1 = new System.Windows.Forms.Button();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            this.textBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
                | System.Windows.Forms.AnchorStyles.Left)
                | System.Windows.Forms.AnchorStyles.Right)));
            this.textBox1.Location = new System.Drawing.Point(8, 40);
            this.textBox1.Multiline = true;
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(391, 242);
            this.textBox1.TabIndex = 0;
            this.textBox1.Text = "";
            button1.Location = new System.Drawing.Point(11, 8);
            button1.Name = "button1";
            button1.Size = new System.Drawing.Size(229, 23);
            button1.TabIndex = 1;
            button1.Text = "Generate string using IndentedTextWriter";
            button1.Click += new System.EventHandler(this.button1_Click);
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(407, 287);
            this.Controls.Add(button1);
            this.Controls.Add(this.textBox1);
            this.Name = "Form1";
            this.Text = "IndentedTextWriter example";
            this.ResumeLayout(false);
        }

        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }
    }
}

Imports System.CodeDom
Imports System.CodeDom.Compiler
Imports System.ComponentModel
Imports System.IO
Imports System.Windows.Forms

Public Class Form1
   Inherits System.Windows.Forms.Form
   Private textBox1 As System.Windows.Forms.TextBox 
   
   Private Function CreateMultilevelIndentString() As String
        ' Create a TextWriter to use as the base output writer.
        Dim baseTextWriter As New System.IO.StringWriter
      
        ' Create an IndentedTextWriter and set the tab string to use 
        ' as the indentation string for each indentation level.
        Dim indentWriter = New IndentedTextWriter(baseTextWriter, "    ")

        ' Set the indentation level.
        indentWriter.Indent = 0

        ' Output test strings at stepped indentations through a recursive loop method.
        WriteLevel(indentWriter, 0, 5)
      
        ' Return the resulting string from the base StringWriter.
        Return baseTextWriter.ToString()
    End Function

    Private Sub WriteLevel(ByVal indentWriter As IndentedTextWriter, ByVal level As Integer, ByVal totalLevels As Integer)
        ' Outputs a test string with a new-line character at the end.
        indentWriter.WriteLine(("This is a test phrase. Current indentation level: " + level.ToString()))

        ' If not yet at the highest recursion level, call this output method for the next level of indentation.
        If level < totalLevels Then
            ' Increase the indentation count for the next level of indented output.
            indentWriter.Indent += 1

            ' Call the WriteLevel method to write test output for the next level of indentation.
            WriteLevel(indentWriter, level + 1, totalLevels)

            ' Restores the indentation count for this level after the recursive branch method has returned.
            indentWriter.Indent -= 1

        Else
            ' Output a string using the WriteLineNoTabs method.
            indentWriter.WriteLineNoTabs("This is a test phrase written with the IndentTextWriter.WriteLineNoTabs method.")
        End If

        ' Outputs a test string with a new-line character at the end.
        indentWriter.WriteLine(("This is a test phrase. Current indentation level: " + level.ToString()))
    End Sub

    Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        textBox1.Text = CreateMultilevelIndentString()
    End Sub

    Public Sub New()
        Dim button1 As New System.Windows.Forms.Button
        Me.textBox1 = New System.Windows.Forms.TextBox
        Me.SuspendLayout()
        Me.textBox1.Anchor = CType(System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Left Or System.Windows.Forms.AnchorStyles.Right, System.Windows.Forms.AnchorStyles)
        Me.textBox1.Location = New System.Drawing.Point(8, 40)
        Me.textBox1.Multiline = True
        Me.textBox1.Name = "textBox1"
        Me.textBox1.Size = New System.Drawing.Size(391, 242)
        Me.textBox1.TabIndex = 0
        Me.textBox1.Text = ""
        button1.Location = New System.Drawing.Point(11, 8)
        button1.Name = "button1"
        button1.Size = New System.Drawing.Size(229, 23)
        button1.TabIndex = 1
        button1.Text = "Generate string using IndentedTextWriter"
        AddHandler button1.Click, AddressOf Me.button1_Click
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(407, 287)
        Me.Controls.Add(button1)
        Me.Controls.Add(Me.textBox1)
        Me.Name = "Form1"
        Me.Text = "IndentedTextWriter example"
        Me.ResumeLayout(False)
    End Sub

    <STAThread()> _
    Shared Sub Main()
        Application.Run(New Form1)
    End Sub
End Class

Observações

IndentedTextWriter Estende A TextWriter fornecendo métodos que inserem uma sequência de tabulação e acompanham o nível atual de indentação. Texto formatado com múltiplos níveis de indentação é útil para código gerado, por isso esta classe é usada por implementações de geradores de código CodeDOM.

A sequência tab é a sequência em que consiste cada indentação. Normalmente, a sequência de tabulação contém espaços em branco.