(转)C#使用itextsharp生成PDF文件

本是古典何须时尚 2023-08-17 17:43 122阅读 0赞

原文链接：https://blog.csdn.net/c79651760/article/details/56480109  
  
  
  
  
  
  
  
前言  
前段时间公司需要实现一个PDF文件下载功能，涉及到页眉页脚，段落，图片的生成。遂使用itextsharp来实现这一功能，但是itextsharp功能强大，类库繁多，特别是5.0版本后关于页眉页脚生成的介绍并不多，研究了好久，才弄成功，写下这篇博客做个记录。  
先来看下最后实现的效果：

下面来看代码  
添加引用：

帮助类的代码，这个类可以直接使用，如果你需要增加或者完善某功能，可以对其进行修改。  
此类使用方法下面做介绍：

public class HeaderAndFooterEvent : PdfPageEventHelper, IPdfPageEvent  
\{  
\#region 静态字段

public static PdfTemplate tpl = null;  
public static bool PAGE\_NUMBER = false;//为True时就生成 页眉和页脚  
public static iTextSharp.text.Rectangle rect = PageSize.A4; //文档大小

/// <summary>  
/// 正文字体  
/// </summary>  
private static Font font;

/// <summary>  
/// 页眉页脚字体  
/// </summary>  
public static string HeaderFooterFontName = "黑体";

/// <summary>  
/// 页头页脚字号  
/// </summary>  
public static int HeaderFooterFontSize = 10;

/// <summary>  
/// 页头页尾字体颜色  
/// </summary>  
public static BaseColor HeaderFooterFontColor = BaseColor.BLACK;

/// <summary>  
/// 左边页眉  
/// </summary>  
public static string HeaderLeft \{ get; set; \}  
/// <summary>  
/// 右边页眉  
/// </summary>  
public static string HeaderRight \{ get; set; \}  
/// <summary>  
/// 左边页脚  
/// </summary>  
public static string FooterLeft \{ get; set; \}  
/// <summary>  
/// 右边页脚  
/// </summary>  
public static string FooterRight \{ get; set; \}

\#endregion

\#region 设置页面大小  
/// <summary>  
/// 设置页面大小  
/// </summary>  
/// <param name="type">页面大小(如"A4")</param>  
public static void SetPageSize(string type)  
\{  
switch (type.Trim())  
\{  
case "A4":  
rect = PageSize.A4;  
break;  
case "A8":  
rect = PageSize.A8;  
break;  
\}  
\}  
\#endregion

\#region 设置字体  
/// <summary>  
/// 设置字体  
/// </summary>  
/// <param name="size">字体大小</param>  
public static void SetFont(BaseColor color, string fontName = "华文中宋", float size = 12, int style = Font.NORMAL)  
\{  
font = new Font(BaseFontAndSize(fontName), size, style, color);  
\}  
\#endregion

\#region 生成页眉页脚

/// <summary>  
/// 关闭一个页面时发生  
/// </summary>  
public override void OnEndPage(PdfWriter writer, Document document)  
\{  
if (PAGE\_NUMBER)  
\{  
Font HeaderFooterFont = FontAndSize(HeaderFooterFontName, HeaderFooterFontSize, Font.NORMAL, HeaderFooterFontColor);  
Phrase header\_left = new Phrase(HeaderLeft, HeaderFooterFont);  
Phrase header\_right = new Phrase(HeaderRight, HeaderFooterFont);

Phrase footer\_left = new Phrase(FooterLeft, HeaderFooterFont);  
Phrase footer\_center = new Phrase("第" + (writer.PageNumber) + "页/共 页", HeaderFooterFont);  
Phrase footer\_right = new Phrase(FooterRight, HeaderFooterFont);

PdfContentByte cb = writer.DirectContent;

//模版 显示总共页数  
cb.AddTemplate(tpl, document.Right - 290 + document.LeftMargin, document.Bottom - 15);//调节模版显示的位置

//页眉显示的位置  
ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, header\_right,  
document.Right - 50 + document.LeftMargin, document.Top + 15, 0);

ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, header\_left,  
document.Right - 500 + document.LeftMargin, document.Top + 15, 0);

//页脚显示的位置  
ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, footer\_left,  
document.Right - 535 + document.LeftMargin, document.Bottom - 15, 0);

ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, footer\_center,  
document.Right - 300 + document.LeftMargin, document.Bottom - 15, 0);

ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, footer\_right,  
document.Right - 80 + document.LeftMargin, document.Bottom - 15, 0);  
\}  
\}

/// <summary>  
/// 打开一个新页面时发生  
/// </summary>  
public override void OnStartPage(PdfWriter writer, Document document)  
\{  
if (PAGE\_NUMBER)  
\{  
writer.PageCount = writer.PageNumber - 1;  
\}  
\}

/// <summary>  
/// 关闭PDF文档时发生该事件  
/// </summary>  
public override void OnCloseDocument(PdfWriter writer, Document document)  
\{  
BaseFont bf = BaseFontAndSize(HeaderFooterFontName);  
tpl.BeginText();  
tpl.SetFontAndSize(bf, HeaderFooterFontSize);  
tpl.ShowText((writer.PageNumber - 1).ToString());//总页数  
tpl.EndText();  
tpl.ClosePath();  
\}  
\#endregion

\#region 私有方法

private static Font FontAndSize(string font\_name, int size, int style, BaseColor baseColor)  
\{  
BaseFont baseFont;  
BaseFont.AddToResourceSearch("iTextAsian.dll");  
BaseFont.AddToResourceSearch("iTextAsianCmaps.dll");  
Font font = null;  
string file\_name = "";  
int fontStyle;  
switch (font\_name)  
\{  
case "黑体":  
file\_name = "SIMHEI.TTF";  
break;  
case "华文中宋":  
file\_name = "STZHONGS.TTF";  
break;  
case "宋体":  
file\_name = "SIMYOU.TTF";  
break;  
default:  
file\_name = "SIMYOU.TTF";  
break;  
\}  
baseFont = BaseFont.CreateFont(@"c:/windows/fonts/" + file\_name, BaseFont.IDENTITY\_H, BaseFont.NOT\_EMBEDDED);

if (style < -1)  
\{  
fontStyle = Font.NORMAL;  
\}  
else  
\{  
fontStyle = style;  
\}  
font = new Font(baseFont, size, fontStyle, baseColor);  
return font;  
\}  
private static BaseFont BaseFontAndSize(string font\_name)  
\{  
BaseFont baseFont;  
BaseFont.AddToResourceSearch("iTextAsian.dll");  
BaseFont.AddToResourceSearch("iTextAsianCmaps.dll");  
string file\_name = "";  
switch (font\_name)  
\{  
case "黑体":  
file\_name = "SIMHEI.TTF";  
break;  
case "华文中宋":  
file\_name = "STZHONGS.TTF";  
break;  
case "宋体":  
file\_name = "SIMYOU.TTF";  
break;  
default:  
file\_name = "SIMYOU.TTF";  
break;  
\}  
baseFont = BaseFont.CreateFont(@"c:/windows/fonts/" + file\_name, BaseFont.IDENTITY\_H, BaseFont.NOT\_EMBEDDED);  
return baseFont;  
\}

\#endregion

\#region 添加段落

/// <summary>  
/// 添加段落  
/// </summary>  
/// <param name="content">内容</param>  
/// <param name="Alignment">对齐方式（1为居中，0为居左，2为居右）</param>  
/// <param name="SpacingAfter">段后空行数（0为默认值）</param>  
/// <param name="SpacingBefore">段前空行数（0为默认值）</param>  
/// <param name="MultipliedLeading">行间距（0为默认值）</param>  
public static Paragraph AddParagraph(string content, int Alignment, float SpacingAfter, float SpacingBefore, float MultipliedLeading)  
\{  
Paragraph pra = new Paragraph(content, font);  
pra.Alignment = Alignment;  
pra.SpacingAfter = SpacingAfter;  
pra.SpacingBefore = SpacingBefore;  
pra.MultipliedLeading = MultipliedLeading;  
return pra;  
\}

public static Paragraph AddParagraph(string content, int Alignment, float MultipliedLeading)  
\{  
Paragraph pra = new Paragraph(content, font);  
pra.Alignment = Alignment;  
pra.MultipliedLeading = MultipliedLeading;  
return pra;  
\}

public static void AddPhrase(PdfWriter writer, Document document, string content, float marginLift, float marginBottom)  
\{  
Phrase phrase = new Phrase(content, font);

PdfContentByte cb = writer.DirectContent;  
ColumnText.ShowTextAligned(cb, Element.ALIGN\_CENTER, phrase,  
marginLift + document.LeftMargin, marginBottom, 0);

\#endregion

\#region 添加图片  
/// <summary>  
/// 添加图片  
/// <param name="Alignment">对齐方式 (0/1/2)</param>  
/// <param name="marginRight">页边距</param>  
/// <param name="marginBottom">页边距</param>  
/// </summary>  
public static iTextSharp.text.Image AddImage(string path, int Alignment, float marginRight, float marginBottom)  
\{  
Image img = Image.GetInstance(new Uri(path));  
img.Alignment = Alignment;  
//等比缩放，宽与高的缩放系数哪个大就取哪一个（比如高的系数是0.8，宽的是0.7，则取0.7。这样图片就不会超出页面范围）  
if (img.Width > img.Height)  
\{  
//这里计算图片的缩放系数，因为图片width>height,所以将图片旋转90度以适应页面，计算缩放系数的时候宽与高对调  
float PageHeight = PageSize.A4.Height - marginBottom \* 3;  
double percentHeight = Math.Round((PageHeight / img.Width), 2);

float PageWidth = PageSize.A4.Width - marginRight \* 2;  
double percentWidth = Math.Round((PageWidth / img.Height), 2);

double percent = percentHeight > percentWidth ? percentWidth : percentHeight;  
img.ScalePercent((float)percent \* 100);  
img.RotationDegrees = 90f;  
\}  
else  
\{  
float PageHeight = PageSize.A4.Height - marginBottom \* 3;  
double percentHeight = Math.Round((PageHeight / img.Height), 2);

float PageWidth = PageSize.A4.Width - marginRight \* 2;  
double percentWidth = Math.Round((PageWidth / img.Width), 2);

double percent = percentHeight > percentWidth ? percentWidth : percentHeight;  
img.ScalePercent((float)percent \* 100);  
\}  
return img;  
\}  
\#endregion

\}123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291

下面是使用方法：

在你需要生成文件的地方实例化Document和PdfWriter 对象：

Document document = new Document(HeaderAndFooterEvent.rect);  
//此处使用的是http请求的流，你也可以使用文件流Stream  
PdfWriter writer = PdfWriter.GetInstance(document, HttpContext.Current.Response.OutputStream);  
document.Open();  
writer.PageEvent = new HeaderAndFooterEvent();12345

实现页眉和页脚：

HeaderAndFooterEvent.PAGE\_NUMBER = true;//实现页眉跟页脚  
HeaderAndFooterEvent.tpl = writer.DirectContent.CreateTemplate(500, 500); //定义模板

HeaderAndFooterEvent.HeaderLeft = "Aviation Meteorological Center";  
HeaderAndFooterEvent.HeaderRight = "民航气象中心";  
HeaderAndFooterEvent.FooterLeft = "TEL:010-87922095";  
HeaderAndFooterEvent.FooterRight = \_dtm.ToString("yyyy-MM-dd HH:mm:ss") + "(UTC)";1234567

首页

//每次在添加文本内容之前可以先设置字体，有效期持续到重新设置之前  
HeaderAndFooterEvent.SetFont(BaseColor.BLACK, "宋体", 25, Font.BOLD);  
//添加一个空段落来占位，五个参数分别为：内容，对齐方式（1为居中，0为居左，2为居右），段后空行数，段前空行数，行间距  
document.Add(HeaderAndFooterEvent.AddParagraph(" ", 1, 200, 0, 1.5f));

//这个方法为上一个方法的重载，三个参数分别为：内容，对齐方式，行间距  
document.Add(HeaderAndFooterEvent.AddParagraph("飞行气象文件", 1, 1.5f));  
HeaderAndFooterEvent.SetFont(BaseColor.BLACK, "宋体", 18, Font.BOLD);  
document.Add(HeaderAndFooterEvent.AddParagraph("Meteorological Aviation Report", 1, 1.5f));123456789

然后就是新建页了，每需要一页的时候就 document.NewPage(); 就可以了，当然，如果你在其中一页添加的内容超过了此页的篇幅，则会自动追加一页。下面演示怎么新建一页并添加内容：

document.NewPage();

HeaderAndFooterEvent.SetFont(BaseColor.DARK\_GRAY, "宋体", 15, Font.BOLD);  
document.Add(HeaderAndFooterEvent.AddParagraph("飞行气象文件", 1, 1.5f));  
HeaderAndFooterEvent.SetFont(BaseColor.DARK\_GRAY, "宋体", 12);  
document.Add(HeaderAndFooterEvent.AddParagraph("航班号： " ));  
1234567

下面演示添加图片：  
添加图片比较简单，当图片的宽度超过高度时，会进行旋转并按照比例缩放，从而尽量铺满整个页面。如果你不需要旋转，可以对帮助类进行修改。

document.NewPage();

//四个参数分别为：图片路径，对齐方式，文档的右边距，下边距；边距这两个参数用于计算图片的缩放尺寸。  
document.Add("图片路径", 0, document.RightMargin, document.Bottom));1234

到现在，大功告成  
只需要关闭文档和流就行了。

writer.Flush();  
writer.CloseStream = true;  
document.Close();  
————————————————  
版权声明：本文为CSDN博主「飞翔的牛魔王」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。  
原文链接：https://blog.csdn.net/c79651760/article/details/56480109

转载于:https://www.cnblogs.com/zhangyuG/p/11477126.html