当我们创建PDF图层时,Spire.PDF允许开发人员将该层设置初始可见性状态。同时它还支持设置PDF图层可见属性。本文将详细介绍如何使用C#显示或隐藏现有的PDF图层。
我们可以通过设置PdfLayer.Visibility 属性来设置图层隐藏或显示. 显示图层需要将 PdfLayer.Visibility 设置为 PdfVisibility.On. 隐藏图层需要将PdfLayer.Visibility 设置为PdfVisibility.Off.
按索引或名称隐藏图层:
C#
//加载示例文档
PdfDocument doc = new PdfDocument();
doc.LoadFromFile("AddLayers.pdf");
//隐藏第一个图层
doc.Layers[0].Visibility = PdfVisibility.Off;
//隐藏名为Blue line的图层
doc.Layers["Blue line"].Visibility = PdfVisibility.Off;
//保存文档
doc.SaveToFile("HideLayer.pdf");
VB.NET
'加载示例文档
Dim doc As New PdfDocument()
doc.LoadFromFile("AddLayers.pdf")
'隐藏第一个图层
doc.Layers(0).Visibility = PdfVisibility.Off
'隐藏名为Blue line的图层
doc.Layers("Blue line").Visibility = PdfVisibility.Off
'保存文档
doc.SaveToFile("HideLayer.pdf")
显示或隐藏所有图层:
C#
//加载示例文档
PdfDocument doc = new PdfDocument();
doc.LoadFromFile("AddLayers.pdf");
for (int i = 0; i < doc.Layers.Count; i++)
{
//显示所有图层
//doc.Layers[i].Visibility = PdfVisibility.On;
//隐藏所有图层
doc.Layers[i].Visibility = PdfVisibility.Off;
}
//保存文档
doc.SaveToFile("HideAllLayers.pdf");
VB.NET
'加载示例文档
Dim doc As New PdfDocument()
doc.LoadFromFile("AddLayers.pdf")
For i As Integer = 0 To doc.Layers.Count - 1
'显示所有图层
'doc.Layers[i].Visibility = PdfVisibility.On;
'隐藏所有图层
doc.Layers(i).Visibility = PdfVisibility.Off
Next
'保存文档
doc.SaveToFile("HideAllLayers.pdf")