C#设置PDF表单不可编辑以及提取表单数据的操作

using Spire.Pdf;
 
namespace FlattenAllFormFields
{
    class Program
    {
        static void Main(string[] args)
        {
            //加载PDF文件
            PdfDocument pdf = new PdfDocument();
            pdf.LoadFromFile("PDF表单.pdf");
 
            //设置所有表单不可编辑
            pdf.Form.IsFlatten = true;
 
            //保存生成文件
            pdf.SaveToFile("扁平PDF.pdf");
        }
    }
}

            //获取PDF表单
            PdfFormWidget formWidget = (PdfFormWidget)pdf.Form;
 
            //通过表单名获取指定表单域
            PdfField form = formWidget.FieldsWidget["姓名"];
 
            //通过索引获取指定表单域
            PdfField form = formWidget.FieldsWidget.List[0] as PdfField;
 
            //设置表单不可编辑
            form.Flatten = true;

using Spire.Pdf;
using Spire.Pdf.Fields;
using Spire.Pdf.Widget;
using System.IO;
using System.Text;
 
namespace ExtractFormFieldValues
{
    internal class Program
    {
        static void Main(string[] args)
        {
            //加载PDF文件
            PdfDocument doc = new PdfDocument();
            doc.LoadFromFile("PDF表单.pdf");
 
            //创建StringBuilder对象
            StringBuilder sb = new StringBuilder();
 
            //获取PDF表单
            PdfFormWidget formWidget = doc.Form as PdfFormWidget;
 
            //遍历表单
            for (int i = 0; i < formWidget.FieldsWidget.List.Count; i++)
            {
                PdfField field = formWidget.FieldsWidget.List[i] as PdfField;
 
                //获取文本框的名称和值
                if (field is PdfTextBoxFieldWidget)
                {
                    PdfTextBoxFieldWidget textBoxField = field as PdfTextBoxFieldWidget;
                    string name = textBoxField.Name;
                    string value = textBoxField.Text;
                    sb.Append("文本框名称: " + name + "\r\n");
                    sb.Append("文本框内容: " + value + "\r\n");
                }
 
                //获取列表框的名称、项目和选定项
                if (field is PdfListBoxWidgetFieldWidget)
                {
                    PdfListBoxWidgetFieldWidget listBoxField = field as PdfListBoxWidgetFieldWidget;
                    string name = listBoxField.Name;
                    sb.Append("列表框名称: " + name + "\r\n");
                    sb.Append("列表框项目: \r\n");
 
                    PdfListWidgetItemCollection items = listBoxField.Values;
 
                    foreach (PdfListWidgetItem item in items)
                    {
                        sb.Append(item.Value + "\r\n");
                    }
                    string selectedValue = listBoxField.SelectedValue;
                    sb.Append("列表框选定项: " + selectedValue + "\r\n");
                }
 
                //获取组合框字段的名称、项目和选定项
                if (field is PdfComboBoxWidgetFieldWidget)
                {
                    PdfComboBoxWidgetFieldWidget comBoxField = field as PdfComboBoxWidgetFieldWidget;
                    string name = comBoxField.Name;
                    sb.Append("组合框名称: " + name + "\r\n");
                    sb.Append("组合框项目: \r\n");
                    PdfListWidgetItemCollection items = comBoxField.Values;
 
                    foreach (PdfListWidgetItem item in items)
                    {
                        sb.Append(item.Value + "\r\n");
                    }
                    string selectedValue = comBoxField.SelectedValue;
                    sb.Append("组合框选定项: " + selectedValue + "\r\n");
 
                }
 
                //获取单选按钮的名称和所选项
                if (field is PdfRadioButtonListFieldWidget)
                {
                    PdfRadioButtonListFieldWidget radioBtnField = field as PdfRadioButtonListFieldWidget;
                    string name = radioBtnField.Name;
                    sb.Append("单选按钮名称: " + name + "\r\n");
                    string selectedValue = radioBtnField.SelectedValue;
                    sb.Append("单选按钮选定项: " + selectedValue + "\r\n");
                }
 
                //获取复选框的名称和状态
                if (field is PdfCheckBoxWidgetFieldWidget)
                {
                    PdfCheckBoxWidgetFieldWidget checkBoxField = field as PdfCheckBoxWidgetFieldWidget;
                    string name = checkBoxField.Name;
                    sb.Append("复选框名称: " + name + "\r\n");
                    bool status = checkBoxField.Checked;
                    if (status)
                    {
                        sb.Append("复选框状态: 已选中 \r\n");
                    }
                    else
                    {
                        sb.Append("复选框状态: 未选中 \r\n");
                    }
                }
 
                sb.Append("\n");
            }
 
            //将提取的数据写入txt文件
            File.WriteAllText("提取PDF表单.txt", sb.ToString());
            doc.Dispose();
        }
    }
}