我需要在angularjs webapp中自动填写pdf表格。 pdf表单是在应用程序外部生成的，因此我可以根据需要对其进行配置。
在我的应用中，我只需要加载pdf，修改表单字段并展平文件，使其不再像表单一样。
你知道怎么办？
编辑： 我找到了iText，但它是一个不能为我的项目工作的java库（应用程序在平板电脑上运行，因此我正在寻找100％HTML5的东西）
答案 0 :(得分：14)
我找到了一个解决方案......不完美但它应该符合大多数要求。它不使用任何服务器（完全符合隐私要求）或库！首先，PDF必须是1.5版（Acrobat 6.0或更高版本）。原始pdf可以是另一个版本，但是当您创建字段时，必须将其保存为与Acrobat 6.0或更高版本兼容。如果您想确保格式正确，可以查看there
所以，让我们说我有myform.pdf＆＃39;文件（没有表单字段）;我用Acrobat Pro打开它（我有Acrobat Pro 11，但它应该与其他版本一起使用）。我添加字段并使用＆＃39;代码＆＃39;预先填写字段的值（不是字段名称！）。 （唯一文本字符串）。这段代码将通过下面的javascript函数找到/替换为您想要的字符串，所以请说“＆＃39;％address％＆＃39; （您可以添加多个字段，但使用不同的代码来区分字段）。如果要使字段外观平整，请将字段设置为只读。要保存它，请转到文件 - ＆gt;另存为... - ＆gt;优化PDF并选择＆＃34; Acrobat 6.0及更高版本＆＃34;在Make兼容下（弹出窗口的右上角）。
保存文件后，您可以通过在文本编辑器中打开并查找代码（在我的情况下＆＃39;％地址％＆＃39;）来检查格式是否正确。计算出现次数，应该出现三次。
以下功能有三个作用： - 更改字段内容 - 重新计算内容的长度 - 修复交叉引用表
现在这个函数（看看最后的pdf blob的结尾）：
@param证书：您的pdf表格（此变量的格式必须与FileReader兼容）
@param更改：字段更改，[{find：＆＃39;％address％＆＃39 ;,替换：＆＃39; 2386第五街，纽约，美国＆＃39;}，...]
// Works only for PDF 1.5 (Acrobat 6.0 and later)
var fillCertificate = function (certificate, changes) {
// replace a a substring at a specific position
String.prototype.replaceBetween = function(start, end, what) {
return this.substring(0, start) + what + this.substring(end);
};
// format number with zeros at the beginning (n is the number and length is the total length)
var addLeadingZeros = function (n, length) {
var str = (n > 0 ? n : -n) + "";
var zeros = "";
for (var i = length - str.length; i > 0; i--)
zeros += "0";
zeros += str;
return n >= 0 ? zeros : "-" + zeros;
}
// Create the reader first and read the file (call after the onload method)
var reader = new FileReader();
// To change the content of a field, three things must be done; - change the text of the field, - change the length of the content field, - change the cross table reference
reader.onload = function(aEvent) {
var string = aEvent.target.result;
// Let's first change the content and the content's length
var arrayDiff = [];
var char;
for(var foo = 0; foo < changes.length; foo++) {
// Divide the string into a table of character for finding indices
char = new Array(string.length);
for (var int = 0; int < string.length; int++) {
char[int] = string.charAt(int);
}
// Let's find the content's field to change and change it everywhere
var find = changes[foo].find;
var replace = changes[foo].replace;
var lengthDiff = replace.length - find.length;
var search = new RegExp(find, "g");
var match;
var lastElements = [];
var int = 0;
var objectLenPos;
var objectLenEnd;
// Each time you change the content, compute the offset difference (number of characters). We'll add it later for the cross tables
while (match = search.exec(string)) {
arrayDiff.push({index: match.index, diff: lengthDiff});
lastElements.push({index: match.index, diff: lengthDiff});
// Find length object
if(int == 0){
var length = 0;
var index;
while(char[match.index - length] != '\r'){
index = match.index - length;
length++;
}
objectLenPos = index + 10;
length = 0;
while(char[objectLenPos + length] != ' '){
length++;
objectLenEnd = objectLenPos + length;
}
}
int++;
}
var lengthObject = string.slice(objectLenPos, objectLenEnd) + ' 0 obj';
var objectPositionStart = string.search(new RegExp('\\D' + lengthObject, 'g')) + lengthObject.toString().length + 2;
var length = 0;
var objectPositionEnd;
while(char[objectPositionStart + length] != '\r'){
length++;
objectPositionEnd = objectPositionStart + length;
}
// Change the length of the content's field
var lengthString = new RegExp('Length ', "g");
var fieldLength;
var newLength;
string = string.replace(lengthString, function (match, int) {
// The length is between the two positions calculated above
if (int > objectPositionStart && int < objectPositionEnd) {
var length = 0;
var end;
while (char[int + 7 + length] != '/') {
length++;
end = int + 7 + length;
}
fieldLength = string.slice(end - length, end);
newLength = parseInt(fieldLength) + lengthDiff;
if (fieldLength.length != newLength.toString().length) {
arrayDiff.push({index: int, diff: (newLength.toString().length - fieldLength.length)});
}
// Let's modify the length so it's easy to find and replace what interests us; the length number itself
return "Length%";
}
return match;
});
// Replace the length with the new one based on the length difference
string = string.replace('Length%' + fieldLength, 'Length ' + (newLength).toString());
string = string.replace(new RegExp(find, 'g'), replace);
}
// FIND xref and repair cross tables
// Rebuild the table of character
var char = new Array(string.length);
for (var int = 0; int < string.length; int++) {
char[int] = string.charAt(int);
};
// Find XRefStm (cross reference streams)
var regex = /XRefStm/g, result, indices = [];
while ( (result = regex.exec(string)) ) {
indices.push(result.index);
}
// Get the position of the stream
var xrefstmPositions = [];
for(var int = 0; int < indices.length; int++){
var start;
var length = 0;
while(char[indices[int] - 2 - length] != ' '){
start = indices[int] - 2 - length;
length++;
}
var index = parseInt(string.slice(start, start + length));
var tempIndex = parseInt(string.slice(start, start + length));
// Add the offset (consequence of the content changes) to the index
for(var num = 0; num < arrayDiff.length; num++){
if(index > arrayDiff[num].index){
index = index + arrayDiff[num].diff;
}
}
string = string.replaceBetween(start, start + length, index);
// If there is a difference in the string length then update what needs to be updated
if(tempIndex.toString().length != index.toString().length){
arrayDiff.push({index: start, diff: (index.toString().length - tempIndex.toString().length)});
char = new Array(string.length);
for (var int = 0; int < string.length; int++) {
char[int] = string.charAt(int);
};
}
xrefstmPositions.push(index);
}
// Do the same for non-stream
var regex = /startxref/g, result, indices = [];
while ( (result = regex.exec(string)) ) {
indices.push(result.index);
}
for(var int = 0; int < indices.length; int++){
var end;
var length = 0;
while(char[indices[int] + 11 + length] != '\r'){
length++;
end = indices[int] + 11 + length;
}
var index = parseInt(string.slice(end - length, end));
var tempIndex = parseInt(string.slice(end - length, end));
for(var num = 0; num < arrayDiff.length; num++){
if(index > arrayDiff[num].index){
index = index + arrayDiff[num].diff;
}
}
string = string.replaceBetween(end - length, end, index);
if(tempIndex.toString().length != index.toString().length){
arrayDiff.push({index: end - length, diff: (index.toString().length - tempIndex.toString().length)});
char = new Array(string.length);
for (var int = 0; int < string.length; int++) {
char[int] = string.charAt(int);
};
}
xrefstmPositions.push(index);
}
xrefstmPositions.reverse();
var firstObject, objectLength, end;
var offset;
// Updated the cross tables
for(var int = 0; int < xrefstmPositions.length; int++) {
var length = 0;
var end;
if(char[xrefstmPositions[int]] == 'x'){
offset = 6;
} else{
offset = 0;
}
// Get first object index (read pdf documentation)
while(char[xrefstmPositions[int] + offset + length] != ' '){
length++;
end = xrefstmPositions[int] + offset + length;
}
firstObject = string.slice(end - length, end);
// Get length of objects (read pdf documentation)
length = 0;
while(char[xrefstmPositions[int] + offset + 1 + firstObject.length + length] != '\r'){
length++;
end = xrefstmPositions[int] + offset + 1 + firstObject.length + length;
}
objectLength = string.slice(end - length, end);
// Replace the offset by adding the differences from the content's field
for(var num = 0; num < objectLength; num++){
if(char[xrefstmPositions[int]] == 'x'){
offset = 9;
} else{
offset = 3;
}
// Check if it's an available object
if (char[xrefstmPositions[int] + 17 + offset + firstObject.length + objectLength.length + (num * 20)] == 'n') {
var objectCall = (parseInt(firstObject) + num).toString() + " 0 obj";
var regexp = new RegExp('\\D' + objectCall, "g");
var m;
var lastIndexOf;
// Get the last index in case an object is created more than once. (not very accurate and can be improved)
while (m = regexp.exec(string)) {
lastIndexOf = m.index;
}
string = string.replaceBetween(xrefstmPositions[int] + offset + firstObject.length + objectLength.length + (num * 20), xrefstmPositions[int] + 10 + offset + firstObject.length + objectLength.length + (num * 20), addLeadingZeros(lastIndexOf + 1, 10));
}
if(num == objectLength - 1){
if (char[xrefstmPositions[int] + offset + firstObject.length + objectLength.length + ((num + 1) * 20)] != 't'){
xrefstmPositions.push(xrefstmPositions[int] + offset + firstObject.length + objectLength.length + ((num + 1) * 20));
}
}
}
}
// create a blob from the string
var byteNumbers = new Array(string.length);
for (var int = 0; int < string.length; int++) {
byteNumbers[int] = string.charCodeAt(int);
}
var byteArray = new Uint8Array(byteNumbers);
var blob = new Blob([byteArray], {type : 'application/pdf'});
// Do whatever you want with the blob here
};
reader.readAsBinaryString(certificate);
}
所以代码根本不干净但它有效：）
如果您有任何疑问，请告诉我
答案 1 :(得分：2)
据我所知，平板电脑上没有客户端应用程序可以做到这一点。
这意味着您需要服务器端支持，iText确实是其中的产品之一。另一个是Appligent的FDFMerge，它填充并可以设置为展平。