Dynamic PDF Form Design with C# and .NET

using System;
using System.IO;
using SautinSoft;
using SautinSoft.Pdf;
using SautinSoft.Pdf.Content;

namespace Sample
{
    class Sample
    {
        /// <summary>
        /// Create PDF interactive form fields.
        /// </summary>
        /// <remarks>
        /// Details: https://sautinsoft.com/products/pdf/help/net/developer-guide/create-interactive-form.php
        /// </remarks>
        static void Main(string[] args)
        {
            // Before starting this example, please get a free 100-day trial key:
            // https://sautinsoft.com/start-for-free/

            // Apply the key here:
            // PdfDocument.SetLicense("...");

            using (var document = new PdfDocument())
            {
                var page = document.Pages.Add();

                PdfSize pageSize = page.Size, fieldSize = new PdfSize(150, 20);
                double x = pageSize.Width / 2 - 100, xLabel = x - 5, xField = x + 5, y = pageSize.Height - 50;

                using (var headerText = new PdfFormattedText())
                {
                    // Draw header text.
                    headerText.Font = new PdfFont("Helvetica", 12);
                    headerText.FontWeight = PdfFontWeight.Bold;
                    headerText.MaxTextWidth = pageSize.Width - 100;
                    headerText.AppendLine("PDF Form Example");
                    headerText.FontWeight = PdfFontWeight.Normal;
                    headerText.Append("This is an example of a user fillable PDF form. The fields of this form have been selected to demonstrate as many as possible of the common entry fields.");
                    page.Content.DrawText(headerText, new PdfPoint(50, y - headerText.Height));
                    y -= 100;
                }

                using (var labelText = new PdfFormattedText())
                {
                    labelText.TextAlignment = PdfTextAlignment.Right;
                    labelText.Font = new PdfFont("Helvetica", 12);

                    // Add a 'Full name' label and a 'FullName' text field.
                    labelText.Append("Full name:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var fullNameField = document.Form.Fields.AddText(page, xField, y - (labelText.Height + fieldSize.Height) / 2, fieldSize.Width, fieldSize.Height);
                    fullNameField.Name = "FullName";

                    // Add an 'ID' label and an 'ID' text field that accepts at most 10 characters that are evenly spaced between vertical, comb-like, lines.
                    y -= 40;
                    labelText.Clear();
                    labelText.Append("ID:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var idField = document.Form.Fields.AddText(page, xField, y - (labelText.Height + fieldSize.Height) / 2, fieldSize.Width, fieldSize.Height);
                    idField.Name = "ID";
                    idField.CombOfCharacters = 10;
                    // Make vertical comb-like lines, colored black.
                    idField.Appearance.BorderColor = PdfColors.Black;

                    // Add 'Gender', 'Male', and 'Female' labels and two 'Gender' radio button fields with the choices 'Male' and 'Female'.
                    y -= 40;
                    labelText.Clear();
                    labelText.Append("Gender:");
                    var labelTextHeight = labelText.Height;
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelTextHeight));
                    //document.Form.Fields.NewRadioButtonName = "Gender";
                    var genderMaleField = document.Form.Fields.AddRadioButton(page, xField, y - (labelTextHeight + fieldSize.Height) / 2, fieldSize.Height, fieldSize.Height);
                    genderMaleField.Choice = "Male";
                    genderMaleField.Name = "Gender";
                    labelText.Clear();
                    labelText.TextAlignment = PdfTextAlignment.Left;
                    labelText.Append("Male");
                    page.Content.DrawText(labelText, new PdfPoint(xField + fieldSize.Height + 5, y - (labelTextHeight + labelText.Height) / 2));
                    var genderFemaleField = document.Form.Fields.AddRadioButton(page, xField + fieldSize.Width / 2, y - (labelTextHeight + fieldSize.Height) / 2, fieldSize.Height, fieldSize.Height);
                    genderFemaleField.Choice = "Female";
                    genderFemaleField.Name = "Gender";
                    labelText.Clear();
                    labelText.Append("Female");
                    page.Content.DrawText(labelText, new PdfPoint(xField + fieldSize.Width / 2 + fieldSize.Height + 5, y - (labelTextHeight + labelText.Height) / 2));

                    // Add a 'Married' label and a 'Married' check box field with the export value 'Yes'.
                    y -= 40;
                    labelText.Clear();
                    labelText.TextAlignment = PdfTextAlignment.Right;
                    labelText.Append("Married:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var marriedField = document.Form.Fields.AddCheckBox(page, xField, y - (labelText.Height + fieldSize.Height) / 2, fieldSize.Height, fieldSize.Height);
                    marriedField.Name = "Married";
                    marriedField.ExportValue = "Yes";

                    // Add a 'City' label and a 'City' combo box field that contains several predefined values and allows the user to enter a custom value.
                    y -= 40;
                    labelText.Clear();
                    labelText.Append("City:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var cityField = document.Form.Fields.AddDropdown(page, xField, y - (labelText.Height + fieldSize.Height) / 2, fieldSize.Width, fieldSize.Height);
                    cityField.Name = "City";
                    cityField.Items.Add("New York");
                    cityField.Items.Add("London");
                    cityField.Items.Add("Berlin");
                    cityField.Items.Add("Paris");
                    cityField.Items.Add("Rome");
                    cityField.AllowCustomText = true;

                    // Add a 'Language' label and a 'Language' list box field that contains several predefined values and allows the user to select more than one value.
                    y -= 40;
                    labelText.Clear();
                    labelText.Append("Language:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var languageField = document.Form.Fields.AddListBox(page, xField, y - 60, fieldSize.Width, 60);
                    languageField.Name = "Language";
                    languageField.Items.Add("English");
                    languageField.Items.Add("German");
                    languageField.Items.Add("French");
                    languageField.Items.Add("Italian");
                    languageField.MultipleSelection = true;

                    // Add a 'Notes' label and a 'Notes' text field that may contain multiple lines of text.
                    y -= 80;
                    labelText.Clear();
                    labelText.Append("Notes:");
                    page.Content.DrawText(labelText, new PdfPoint(xLabel, y - labelText.Height));
                    var notesField = document.Form.Fields.AddText(page, xField, y - 80, fieldSize.Width, 80);
                    notesField.Name = "Notes";
                    notesField.MultiLine = true;

                    // Add a 'ResetButton' button field with an action that resets all form fields to their default values.
                    y -= 100;
                    var resetField = document.Form.Fields.AddButton(page, xField, y - fieldSize.Height, fieldSize.Width, fieldSize.Height);
                    resetField.Name = "ResetButton";
                    resetField.Appearance.Label = "Reset";
                    resetField.Actions.AddResetForm();
                }
                // Save PDF Document.
                document.Save("Form.pdf");
            }

            System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo("Form.pdf") { UseShellExecute = true });
        }
    }
}

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