Inserting an array as a table into a Google doc - google-apps-script

Question

I am creating a document from a Template, and cannot figure out how to insert a table at the right position.
I have the table in memory as a 2D array, and in the template I have place-holders like this (including the square-brackets):
...
[TABLE 1]
...
[TABLE 2]
...
[TABLE 3]
...
Each of these placeholders is in a 1x1 table.
I have managed to insert my first array in the right position, but when I then search for the following placeholders my array always gets inserted after Table 1.
My code is the following (I found this online and adapted it slightly):
function insertTable(targetdoc, stringToReplace, tableValues) {
var body = targetdoc.getBody();
var searchElement = targetdoc.getActiveSection();
var searchType = DocumentApp.ElementType.TABLE;
var searchHeading = DocumentApp.ElementType.TABLE_CELL;
var searchResult = null;
// Search until the table is found.
while (searchResult = searchElement.findElement(searchType, searchResult)) {
var par = searchResult.getElement().asTable();
var tabletext = par.getText();
var substr=tabletext.search(stringToReplace);
if (substr >0 ) {
var childindex = body.getChildIndex(par);
var oTable = body.insertTable(childindex+1, tableValues);
return oTable;
}
}
}
and the calling code is:
var oTable = insertTable(oOutputFile,"["+cFieldID+"]",aTable);
where oOutputfile is the new doc, cFieldID is the placeholder text, and aTable is the 2D array.
Can anyone help me get this to work, so that it inserts each array into the correct position?
Thanks

Answer 1

I have written something very similar that might prove useful to you, see GAS Template Engine
It will accept any JSON string and replace place holders in a document that match the structure of the JSON. When an array is encountered, the script looks for a place holder in a table and it will create table rows for each element of the array.
So if your JSON string contains an array as below :
var json = { myarr : [ { col1: "a", col2 : "b" }, { col1 : "c", col2 : "d" }] }
then the script will look for a table in the template document that looks like this :
------------------------------------------------------
| $myarr.col1 | $myarr.col2 |
-------------------------------------------------------
and transform that into :
-----------------------------------
| a | b |
-----------------------------------
| c | d |
-----------------------------------
it will keep the formatting of the rows as well.
It is just a proof of concept for a templating engine but it should be enough to solve your problem.

Answer 2

Thanks koma for your solution which I will certainly use in future, however it was a bit of overkill for what I was looking for.
Finally, I found the solution to what I needed after a mammoth debugging session, and my function shown above has now become:
function insertTable(targetdoc, stringToReplace, tableValues) {
var oDoc = targetdoc.getBody(); // Document
var oSR = oDoc.findText(stringToReplace); // SearchResult
var oPara = oSR.getElement().asText().getParent(); // Paragraph
var nIndex = oDoc.getChildIndex(oPara); // Index
var oTable = oDoc.insertTable(nIndex, tableValues); // Table
return oTable;
}
so, for example, if I have a doc (oDoc) with the following placeholder
[TABLE 1]
an array
aData: {{"","column 1","column 2"},{"row 1","data 11","data 12"},{"row 2","data 21","data 22"}}
and a variable
cFieldID = "TABLE 1";
and call my function
oTable = insertTable(oDoc, cFieldID, aData);
oOutputFile.replaceText("\\["+cFieldID+"\\]","");
I obtain the following in lieu of the placeholder text
-----------------------------------
| | column 1 | column 2 |
-----------------------------------
| row 1 | data 11 | data 12 |
-----------------------------------
| row 2 | data 21 | data 22 |
-----------------------------------
This is less generic and powerful than koma's solution, but sufficient for what I need for now.
Chris