C# 使用itextsharp突出显示PDF文件时出现数字超出范围错误
我在回答以下问题时使用了代码在pdf中突出显示了该单词： 但当我打开这个时，我得到了“一个数字超出范围错误”C# 使用itextsharp突出显示PDF文件时出现数字超出范围错误,c#,pdf,itextsharp,C#,Pdf,Itextsharp,我在回答以下问题时使用了代码在pdf中突出显示了该单词： 但当我打开这个时，我得到了“一个数字超出范围错误” private void hightlightPDFText（） { 尝试 { 字符串[]highlightText=新字符串[]{“延伸”、“地质”}； 字符串inputFile=Server.MapPath（“~/pdf/”）+“101111j174754572003tb00036x.pdf”； 字符串outputFile=Server.MapPath（“~/pdf/”）+“1011
private void hightlightPDFText（）
{
尝试
{
字符串[]highlightText=新字符串[]{“延伸”、“地质”}；
字符串inputFile=Server.MapPath（“~/pdf/”）+“101111j174754572003tb00036x.pdf”；
字符串outputFile=Server.MapPath（“~/pdf/”）+“101111j174754572003tb00036x_Highlighted.pdf”；
//获取输入文档
HighlightPdFanRotation（输入文件、输出文件、highlightText）；
}
捕获（例外情况除外）
{
响应。写入（例如消息）；
}
}
私有void HighlightPdFanRotation（字符串输入文件、字符串输出文件、字符串[]highlightText）
{
尝试
{
PdfReader reader=新PdfReader（输入文件）；
使用（FileStream fs=newfilestream（outputFile，FileMode.Create，FileAccess.Write，FileShare.None））
{
使用（PdfStamper压模=新PdfStamper（读卡器，fs））
{
myLocationTextExtractionStrategy策略=新建myLocationTextExtractionStrategy（）；
int pageCount=reader.NumberOfPages；
对于（int pageno=1；pageno我可以复制这个问题。这不是iTextSharp的问题，而是OP使用的代码的问题；此外，第三方Jcis、in提供的myLocationTextExtractionStrategy
类中可能有问题，或者仅仅是我翻译它的vb-to-c翻译程序中的问题，而不必使用wi混合使用VB和C。此外，OP代码中存在一个问题，导致标记过多
来自的highlightPdFanRotation
中的问题
在这种方法中，我使用
myLocationTextExtractionStrategy strategy = new myLocationTextExtractionStrategy();
无需进一步初始化，但需要初始化一个成员：
strategy.UndercontentHorizontalScaling = 100;
如果不能做到这一点，该策略将使用0默认值。因此，所有字符串宽度计算都将乘以0
在完成这一步后，我将修复答案中的代码
在myLocationTextExtractionStrategy
中发布，至少在我的C版本中
我使用的C#翻译中的myLocationTextExtractionStrategy
方法GetStringWidth
定义为
private float GetStringWidth(string str, float curFontSize, float pSingleSpaceWidth, DocumentFont pFont)
{
char[] chars = str.ToCharArray();
float totalWidth = 0;
float w = 0;
foreach (char c in chars) {
w = pFont.GetWidth(c) / 1000;
totalWidth += (w * curFontSize + this.UndercontentCharacterSpacing) * this.UndercontentHorizontalScaling / 100;
}
return totalWidth;
}
不幸的是，pFont.GetWidth（c）
被定义为返回一个int
；因此，除法pFont.GetWidth（c）/1000
作为一个整数运算执行，因此几乎所有时间的结果都是0（因为字形宽度通常在0和1000之间）。这一行必须更正为：
w = pFont.GetWidth(c) / 1000.0f;
原始VB版本如下所示：
Private Function GetStringWidth(ByVal str As String, ByVal curFontSize As Single, ByVal pSingleSpaceWidth As Single, ByVal pFont As DocumentFont) As Single
Dim chars() As Char = str.ToCharArray()
Dim totalWidth As Single = 0
Dim w As Single = 0
For Each c As Char In chars
w = pFont.GetWidth(c) / 1000
totalWidth += (w * curFontSize + Me.UndercontentCharacterSpacing) * Me.UndercontentHorizontalScaling / 100
Next
Return totalWidth
End Function
/Rect[259.2 679.86 -9223372036854775808 692.58]
我对VB不太了解，无法判断这里的w=pFont.GetWidth（c）/1000
是作为浮点运算还是整数运算计算的。在后一种情况下，这也表明这里存在问题
问题的影响
有趣的是，这两个问题具有相同的效果：GetStringWidth
始终返回0。此方法在GetRectangleFromText
中用于计算校正系数：
'Text Width in User Space Units
Dim LineRealWidth As Single = LastChunk.PosRight - FirstChunk.PosLeft
'Text Width in Text Units
Dim LineTextWidth As Single = GetStringWidth(sTextinChunks, LastChunk.curFontSize, LastChunk.charSpaceWidth, ThisPdfDocFonts.Values.ElementAt(LastChunk.FontIndex))
'TransformationValue value for Interpolation
Dim TransformationValue As Single = LineRealWidth / LineTextWidth
因此，TransformationValue
最终是无穷大的
在某些特殊情况下，此TransformationValue
稍后与偏移相乘，从而生成如下矩形：
Private Function GetStringWidth(ByVal str As String, ByVal curFontSize As Single, ByVal pSingleSpaceWidth As Single, ByVal pFont As DocumentFont) As Single
Dim chars() As Char = str.ToCharArray()
Dim totalWidth As Single = 0
Dim w As Single = 0
For Each c As Char In chars
w = pFont.GetWidth(c) / 1000
totalWidth += (w * curFontSize + Me.UndercontentCharacterSpacing) * Me.UndercontentHorizontalScaling / 100
Next
Return totalWidth
End Function
/Rect[259.2 679.86 -9223372036854775808 692.58]
这超出了Adobe Reader的范围
OP代码中的另一个问题
但是OP的代码中也有一个真正的问题，在这个问题中，他使用了一个全球战略对象
myLocationTextExtractionStrategy strategy = new myLocationTextExtractionStrategy();
int pageCount = reader.NumberOfPages;
for (int pageno = 1; pageno <= pageCount; pageno++)
{
string currentText = PdfTextExtractor.GetTextFromPage(reader, pageno, strategy);
由于我的原因，哪一行会抛出错误？代码不会抛出任何错误。当我在adobe中打开pdf时，它会说“数字超出范围错误”谢谢。你能用c#提供我的LocationTextExtractionsStrategy吗？我在vb.net中将我的LocationTextExtractionsStrategy转换为dll并添加到bin。非常感谢你的帮助，它工作得非常好。如果你能共享一个示例文档，我们可以查看它并确定这些零的原因。我真的（真的）很乐意，但不幸的是，我无法获得所需的权限，而且问题很少发生，我担心在已知的安全文档中复制它可能会花费很长时间（如果有的话）。也就是说，如果有帮助，我可以从我的程序中提供信息，因为我可能会导致调试中出现问题。因此，如果您需要任何程序/变量信息我可以在调用getwidth之前提供，然后我愿意提供。我没有发现任何奇怪的值。在我的实例中，有41个块，错误不是第一个块的一部分。我搜索的文本是“23/07/15”，sTextInUsedChunks=“23/07/15]”-你可能猜对了，我正在突出显示（英国）日期。如果我能提供帮助，请告诉我，但我的初步估计是有效的，因此问题并不紧迫。我需要一种方法来正确重现问题，然后调试itext行为。
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using System.Text;
using iTextSharp.text.pdf;
using iTextSharp.text.pdf.parser;
// how to highlight a text or word in a pdf file using iTextsharp?
// https://stackoverflow.com/questions/6523243/how-to-highlight-a-text-or-word-in-a-pdf-file-using-itextsharp
//
// myLocationTextExtractionStrategy has been shared by Jcis in his answer
// https://stackoverflow.com/a/11076968/1729265
// as VB class. This has been translated to C# using Telerik with some minor
// translation glitch fixes.
namespace iTextSharp_Playground.Content
{
public class myLocationTextExtractionStrategy : ITextExtractionStrategy
{
private float _UndercontentCharacterSpacing = 0;
private float _UndercontentHorizontalScaling = 0;
private SortedList<string, DocumentFont> ThisPdfDocFonts;
public static bool DUMP_STATE = false;
//* a summary of all found text
private List<TextChunk> locationalResult = new List<TextChunk>();
//*
// * Creates a new text extraction renderer.
//
public myLocationTextExtractionStrategy()
{
ThisPdfDocFonts = new SortedList<string, DocumentFont>();
}
//*
// * @see com.itextpdf.text.pdf.parser.RenderListener#beginTextBlock()
//
public virtual void BeginTextBlock()
{
}
//*
// * @see com.itextpdf.text.pdf.parser.RenderListener#endTextBlock()
//
public virtual void EndTextBlock()
{
}
//*
// * @param str
// * @return true if the string starts with a space character, false if the string is empty or starts with a non-space character
//
private bool StartsWithSpace(String str)
{
if (str.Length == 0) {
return false;
}
return str[0] == ' ';
}
//*
// * @param str
// * @return true if the string ends with a space character, false if the string is empty or ends with a non-space character
//
private bool EndsWithSpace(String str)
{
if (str.Length == 0) {
return false;
}
return str[str.Length - 1] == ' ';
}
public float UndercontentCharacterSpacing {
get { return _UndercontentCharacterSpacing; }
set { _UndercontentCharacterSpacing = value; }
}
public float UndercontentHorizontalScaling
{
get { return _UndercontentHorizontalScaling; }
set { _UndercontentHorizontalScaling = value; }
}
public virtual String GetResultantText()
{
if (DUMP_STATE) {
DumpState();
}
locationalResult.Sort();
StringBuilder sb = new StringBuilder();
TextChunk lastChunk = null;
foreach (TextChunk chunk in locationalResult) {
if (lastChunk == null) {
sb.Append(chunk.text);
} else {
if (chunk.SameLine(lastChunk)) {
float dist = chunk.DistanceFromEndOf(lastChunk);
if (dist < -chunk.charSpaceWidth) {
sb.Append(' ');
// we only insert a blank space if the trailing character of the previous string wasn't a space, and the leading character of the current string isn't a space
} else if (dist > chunk.charSpaceWidth / 2f && !StartsWithSpace(chunk.text) && !EndsWithSpace(lastChunk.text)) {
sb.Append(' ');
}
sb.Append(chunk.text);
} else {
sb.Append((char)10);
sb.Append(chunk.text);
}
}
lastChunk = chunk;
}
return sb.ToString();
}
public List<iTextSharp.text.Rectangle> GetTextLocations(string pSearchString, System.StringComparison pStrComp)
{
List<iTextSharp.text.Rectangle> FoundMatches = new List<iTextSharp.text.Rectangle>();
StringBuilder sb = new StringBuilder();
List<TextChunk> ThisLineChunks = new List<TextChunk>();
bool bStart = false;
bool bEnd = false;
TextChunk FirstChunk = null;
TextChunk LastChunk = null;
string sTextInUsedChunks = null;
foreach (TextChunk chunk in locationalResult) {
if (ThisLineChunks.Count > 0 && !chunk.SameLine(ThisLineChunks[ThisLineChunks.Count-1]))
{
if (sb.ToString().IndexOf(pSearchString, pStrComp) > -1) {
string sLine = sb.ToString();
//Check how many times the Search String is present in this line:
int iCount = 0;
int lPos = 0;
lPos = sLine.IndexOf(pSearchString, 0, pStrComp);
while (lPos > -1) {
iCount += 1;
if (lPos + pSearchString.Length > sLine.Length)
break; // TODO: might not be correct. Was : Exit Do
else
lPos = lPos + pSearchString.Length;
lPos = sLine.IndexOf(pSearchString, lPos, pStrComp);
}
//Process each match found in this Text line:
int curPos = 0;
for (int i = 1; i <= iCount; i++) {
string sCurrentText = null;
int iFromChar = 0;
int iToChar = 0;
iFromChar = sLine.IndexOf(pSearchString, curPos, pStrComp);
curPos = iFromChar;
iToChar = iFromChar + pSearchString.Length - 1;
sCurrentText = null;
sTextInUsedChunks = null;
FirstChunk = null;
LastChunk = null;
//Get first and last Chunks corresponding to this match found, from all Chunks in this line
foreach (TextChunk chk in ThisLineChunks) {
sCurrentText = sCurrentText + chk.text;
//Check if we entered the part where we had found a matching String then get this Chunk (First Chunk)
if (!bStart && sCurrentText.Length - 1 >= iFromChar) {
FirstChunk = chk;
bStart = true;
}
//Keep getting Text from Chunks while we are in the part where the matching String had been found
if (bStart & !bEnd) {
sTextInUsedChunks = sTextInUsedChunks + chk.text;
}
//If we get out the matching String part then get this Chunk (last Chunk)
if (!bEnd && sCurrentText.Length - 1 >= iToChar) {
LastChunk = chk;
bEnd = true;
}
//If we already have first and last Chunks enclosing the Text where our String pSearchString has been found
//then it's time to get the rectangle, GetRectangleFromText Function below this Function, there we extract the pSearchString locations
if (bStart & bEnd) {
FoundMatches.Add(GetRectangleFromText(FirstChunk, LastChunk, pSearchString, sTextInUsedChunks, iFromChar, iToChar, pStrComp));
curPos = curPos + pSearchString.Length;
bStart = false;
bEnd = false;
break; // TODO: might not be correct. Was : Exit For
}
}
}
}
sb.Clear();
ThisLineChunks.Clear();
}
ThisLineChunks.Add(chunk);
sb.Append(chunk.text);
}
return FoundMatches;
}
private iTextSharp.text.Rectangle GetRectangleFromText(TextChunk FirstChunk, TextChunk LastChunk, string pSearchString, string sTextinChunks, int iFromChar, int iToChar, System.StringComparison pStrComp)
{
//There are cases where Chunk contains extra text at begining and end, we don't want this text locations, we need to extract the pSearchString location inside
//for these cases we need to crop this String (left and Right), and measure this excedent at left and right, at this point we don't have any direct way to make a
//Transformation from text space points to User Space units, the matrix for making this transformation is not accesible from here, so for these special cases when
//the String needs to be cropped (Left/Right) We'll interpolate between the width from Text in Chunk (we have this value in User Space units), then i'll measure Text corresponding
//to the same String but in Text Space units, finally from the relation betweeenthese 2 values I get the TransformationValue I need to use for all cases
//Text Width in User Space Units
float LineRealWidth = LastChunk.PosRight - FirstChunk.PosLeft;
//Text Width in Text Units
float LineTextWidth = GetStringWidth(sTextinChunks, LastChunk.curFontSize, LastChunk.charSpaceWidth, ThisPdfDocFonts.Values[LastChunk.FontIndex]);
//TransformationValue value for Interpolation
float TransformationValue = LineRealWidth / LineTextWidth;
//In the worst case, we'll need to crop left and right:
int iStart = sTextinChunks.IndexOf(pSearchString, pStrComp);
int iEnd = iStart + pSearchString.Length - 1;
string sLeft = null;
if (iStart == 0)
sLeft = null;
else
sLeft = sTextinChunks.Substring(0, iStart);
string sRight = null;
if (iEnd == sTextinChunks.Length - 1)
sRight = null;
else
sRight = sTextinChunks.Substring(iEnd + 1, sTextinChunks.Length - iEnd - 1);
//Measure cropped Text at left:
float LeftWidth = 0;
if (iStart > 0) {
LeftWidth = GetStringWidth(sLeft, LastChunk.curFontSize, LastChunk.charSpaceWidth, ThisPdfDocFonts.Values[LastChunk.FontIndex]);
LeftWidth = LeftWidth * TransformationValue;
}
//Measure cropped Text at right:
float RightWidth = 0;
if (iEnd < sTextinChunks.Length - 1) {
RightWidth = GetStringWidth(sRight, LastChunk.curFontSize, LastChunk.charSpaceWidth, ThisPdfDocFonts.Values[LastChunk.FontIndex]);
RightWidth = RightWidth * TransformationValue;
}
//LeftWidth is the text width at left we need to exclude, FirstChunk.distParallelStart is the distance to left margin, both together will give us this LeftOffset
float LeftOffset = FirstChunk.distParallelStart + LeftWidth;
//RightWidth is the text width at right we need to exclude, FirstChunk.distParallelEnd is the distance to right margin, we substract RightWidth from distParallelEnd to get RightOffset
float RightOffset = LastChunk.distParallelEnd - RightWidth;
//Return this Rectangle
return new iTextSharp.text.Rectangle(LeftOffset, FirstChunk.PosBottom, RightOffset, FirstChunk.PosTop);
}
private float GetStringWidth(string str, float curFontSize, float pSingleSpaceWidth, DocumentFont pFont)
{
char[] chars = str.ToCharArray();
float totalWidth = 0;
float w = 0;
foreach (char c in chars) {
w = pFont.GetWidth(c) / 1000f;
totalWidth += (w * curFontSize + this.UndercontentCharacterSpacing) * this.UndercontentHorizontalScaling / 100;
}
return totalWidth;
}
private void DumpState()
{
foreach (TextChunk location in locationalResult) {
location.PrintDiagnostics();
Console.WriteLine();
}
}
public virtual void RenderText(TextRenderInfo renderInfo)
{
LineSegment segment = renderInfo.GetBaseline();
TextChunk location = new TextChunk(renderInfo.GetText(), segment.GetStartPoint(), segment.GetEndPoint(), renderInfo.GetSingleSpaceWidth());
var _with1 = location;
//Chunk Location:
// Debug.Print(renderInfo.GetText);
_with1.PosLeft = renderInfo.GetDescentLine().GetStartPoint()[Vector.I1];
_with1.PosRight = renderInfo.GetAscentLine().GetEndPoint()[Vector.I1];
_with1.PosBottom = renderInfo.GetDescentLine().GetStartPoint()[Vector.I2];
_with1.PosTop = renderInfo.GetAscentLine().GetEndPoint()[Vector.I2];
//Chunk Font Size: (Height)
_with1.curFontSize = _with1.PosTop - segment.GetStartPoint()[Vector.I2];
//Use Font name and Size as Key in the SortedList
string StrKey = renderInfo.GetFont().PostscriptFontName + _with1.curFontSize.ToString();
//Add this font to ThisPdfDocFonts SortedList if it's not already present
if (!ThisPdfDocFonts.ContainsKey(StrKey))
ThisPdfDocFonts.Add(StrKey, renderInfo.GetFont());
//Store the SortedList index in this Chunk, so we can get it later
_with1.FontIndex = ThisPdfDocFonts.IndexOfKey(StrKey);
locationalResult.Add(location);
}
//*
// * Represents a chunk of text, it's orientation, and location relative to the orientation vector
//
public class TextChunk : IComparable<TextChunk>
{
//* the text of the chunk
internal String text;
//* the starting location of the chunk
internal Vector startLocation;
//* the ending location of the chunk
internal Vector endLocation;
//* unit vector in the orientation of the chunk
internal Vector orientationVector;
//* the orientation as a scalar for quick sorting
internal int orientationMagnitude;
//* perpendicular distance to the orientation unit vector (i.e. the Y position in an unrotated coordinate system)
// * we round to the nearest integer to handle the fuzziness of comparing floats
internal int distPerpendicular;
//* distance of the start of the chunk parallel to the orientation unit vector (i.e. the X position in an unrotated coordinate system)
internal float distParallelStart;
//* distance of the end of the chunk parallel to the orientation unit vector (i.e. the X position in an unrotated coordinate system)
internal float distParallelEnd;
//* the width of a single space character in the font of the chunk
internal float charSpaceWidth;
private float _PosLeft;
private float _PosRight;
private float _PosTop;
private float _PosBottom;
private float _curFontSize;
private int _FontIndex;
public int FontIndex {
get { return _FontIndex; }
set { _FontIndex = value; }
}
public float PosLeft {
get { return _PosLeft; }
set { _PosLeft = value; }
}
public float PosRight {
get { return _PosRight; }
set { _PosRight = value; }
}
public float PosTop {
get { return _PosTop; }
set { _PosTop = value; }
}
public float PosBottom {
get { return _PosBottom; }
set { _PosBottom = value; }
}
public float curFontSize {
get { return _curFontSize; }
set { _curFontSize = value; }
}
public TextChunk(String str, Vector startLocation, Vector endLocation, float charSpaceWidth)
{
this.text = str;
this.startLocation = startLocation;
this.endLocation = endLocation;
this.charSpaceWidth = charSpaceWidth;
Vector oVector = endLocation.Subtract(startLocation);
if (oVector.Length == 0) {
oVector = new Vector(1, 0, 0);
}
orientationVector = oVector.Normalize();
orientationMagnitude = Convert.ToInt32(Math.Truncate(Math.Atan2(orientationVector[Vector.I2], orientationVector[Vector.I1]) * 1000));
Vector origin = new Vector(0, 0, 1);
distPerpendicular = Convert.ToInt32((startLocation.Subtract(origin)).Cross(orientationVector)[Vector.I3]);
distParallelStart = orientationVector.Dot(startLocation);
distParallelEnd = orientationVector.Dot(endLocation);
}
public void PrintDiagnostics()
{
Console.WriteLine("Text (@" + Convert.ToString(startLocation) + " -> " + Convert.ToString(endLocation) + "): " + text);
Console.WriteLine("orientationMagnitude: " + orientationMagnitude);
Console.WriteLine("distPerpendicular: " + distPerpendicular);
Console.WriteLine("distParallel: " + distParallelStart);
}
//*
// * @param as the location to compare to
// * @return true is this location is on the the same line as the other
//
public bool SameLine(TextChunk a)
{
if (orientationMagnitude != a.orientationMagnitude) {
return false;
}
if (distPerpendicular != a.distPerpendicular) {
return false;
}
return true;
}
//*
// * Computes the distance between the end of 'other' and the beginning of this chunk
// * in the direction of this chunk's orientation vector. Note that it's a bad idea
// * to call this for chunks that aren't on the same line and orientation, but we don't
// * explicitly check for that condition for performance reasons.
// * @param other
// * @return the number of spaces between the end of 'other' and the beginning of this chunk
//
public float DistanceFromEndOf(TextChunk other)
{
float distance = distParallelStart - other.distParallelEnd;
return distance;
}
//*
// * Compares based on orientation, perpendicular distance, then parallel distance
// * @see java.lang.Comparable#compareTo(java.lang.Object)
//
public int CompareTo(TextChunk rhs)
{
if (object.ReferenceEquals(this, rhs)) {
return 0;
}
// not really needed, but just in case
int rslt = 0;
rslt = CompareInts(orientationMagnitude, rhs.orientationMagnitude);
if (rslt != 0) {
return rslt;
}
rslt = CompareInts(distPerpendicular, rhs.distPerpendicular);
if (rslt != 0) {
return rslt;
}
// note: it's never safe to check floating point numbers for equality, and if two chunks
// are truly right on top of each other, which one comes first or second just doesn't matter
// so we arbitrarily choose this way.
rslt = distParallelStart < rhs.distParallelStart ? -1 : 1;
return rslt;
}
//*
// *
// * @param int1
// * @param int2
// * @return comparison of the two integers
//
private static int CompareInts(int int1, int int2)
{
return int1 == int2 ? 0 : int1 < int2 ? -1 : 1;
}
}
//*
// * no-op method - this renderer isn't interested in image events
// * @see com.itextpdf.text.pdf.parser.RenderListener#renderImage(com.itextpdf.text.pdf.parser.ImageRenderInfo)
// * @since 5.0.1
//
public void RenderImage(ImageRenderInfo renderInfo)
{
// do nothing
}
}
}
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