Count

FieldCollection.Count property

返回集合中字段的数量。

public int Count { get; }

例子

演示如何从字段集合中删除字段。

Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);

builder.InsertField(" DATE \\@ \"dddd, d MMMM yyyy\" ");
builder.InsertField(" TIME ");
builder.InsertField(" REVNUM ");
builder.InsertField(" AUTHOR  \"John Doe\" ");
builder.InsertField(" SUBJECT \"My Subject\" ");
builder.InsertField(" QUOTE \"Hello world!\" ");
doc.UpdateFields();

FieldCollection fields = doc.Range.Fields;

Assert.AreEqual(6, fields.Count);

// 下面是从字段集合中删除字段的四种方法。
// 1 - 获取一个字段来删除自身：
fields[0].Remove();
Assert.AreEqual(5, fields.Count);

// 2 - 获取集合以删除我们传递给其删除方法的字段：
Field lastField = fields[3];
fields.Remove(lastField);
Assert.AreEqual(4, fields.Count);

// 3 - 从索引处的集合中删除字段：
fields.RemoveAt(2);
Assert.AreEqual(3, fields.Count);

// 4 - 立即从集合中删除所有字段：
fields.Clear();
Assert.AreEqual(0, fields.Count);

展示如何使用字段集合。

public void FieldCollection()
{
    Document doc = new Document();
    DocumentBuilder builder = new DocumentBuilder(doc);

    builder.InsertField(" DATE \\@ \"dddd, d MMMM yyyy\" ");
    builder.InsertField(" TIME ");
    builder.InsertField(" REVNUM ");
    builder.InsertField(" AUTHOR  \"John Doe\" ");
    builder.InsertField(" SUBJECT \"My Subject\" ");
    builder.InsertField(" QUOTE \"Hello world!\" ");
    doc.UpdateFields();

    FieldCollection fields = doc.Range.Fields;

    Assert.AreEqual(6, fields.Count);

    // 遍历字段集合，并打印内容和类型
    // 使用自定义访问者实现的每个字段。
    FieldVisitor fieldVisitor = new FieldVisitor();

    using (IEnumerator<Field> fieldEnumerator = fields.GetEnumerator())
    {
        while (fieldEnumerator.MoveNext())
        {
            if (fieldEnumerator.Current != null)
            {
                fieldEnumerator.Current.Start.Accept(fieldVisitor);
                fieldEnumerator.Current.Separator?.Accept(fieldVisitor);
                fieldEnumerator.Current.End.Accept(fieldVisitor);
            }
            else
            {
                Console.WriteLine("There are no fields in the document.");
            }
        }
    }

    Console.WriteLine(fieldVisitor.GetText());
}

/// <summary>
/// 打印字段信息的文档访问者实现。
/// </summary>
public class FieldVisitor : DocumentVisitor
{
    public FieldVisitor()
    {
        mBuilder = new StringBuilder();
    }

    /// <summary>
    /// 获取访问者积累的文档的纯文本。
    /// </summary>
    public string GetText()
    {
        return mBuilder.ToString();
    }

    /// <summary>
    /// 在文档中遇到 FieldStart 节点时调用。
    /// </summary>
    public override VisitorAction VisitFieldStart(FieldStart fieldStart)
    {
        mBuilder.AppendLine("Found field: " + fieldStart.FieldType);
        mBuilder.AppendLine("\tField code: " + fieldStart.GetField().GetFieldCode());
        mBuilder.AppendLine("\tDisplayed as: " + fieldStart.GetField().Result);

        return VisitorAction.Continue;
    }

    /// <summary>
    /// 在文档中遇到 FieldSeparator 节点时调用。
    /// </summary>
    public override VisitorAction VisitFieldSeparator(FieldSeparator fieldSeparator)
    {
        mBuilder.AppendLine("\tFound separator: " + fieldSeparator.GetText());

        return VisitorAction.Continue;
    }

    /// <summary>
    /// 在文档中遇到 FieldEnd 节点时调用。
    /// </summary>
    public override VisitorAction VisitFieldEnd(FieldEnd fieldEnd)
    {
        mBuilder.AppendLine("End of field: " + fieldEnd.FieldType);

        return VisitorAction.Continue;
    }

    private readonly StringBuilder mBuilder;
}

也可以看看

FieldCollection.Item