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Xojo Plugin Requires Chilkat v11.7.0+

Fill a PDF Template: Replace {{placeholders}} with Values

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Demonstrates the TextReplace method on an invoice template whose values are written as placeholders such as {{customer}} and {{total}}. The "placeholders" object names each placeholder and the text to put in; every occurrence on the page is replaced, including a placeholder inside a sentence or inside a label such as "Tax ({{taxRate}}):". The text is redrawn with the font the template used, so the result looks like the template, and a value that is right-aligned in the template stays right-aligned. The changes are written by WriteFile.

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Xojo Plugin
Dim success As Boolean
success = False

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  The PDF used in this example is available at invoice_template.pdf

Dim pdf As New Chilkat.Pdf
success = pdf.LoadFile("qa_data/pdf/invoice_template.pdf")
If (success = False) Then
    System.DebugLog(pdf.LastErrorText)
    Return
End If

//  The template has these placeholders in its page text:
//    {{customer}} (twice: "Bill To:" and the closing sentence), {{date}}, {{po}},
//    two item rows: {{qty1}} {{desc1}} {{price1}} {{amount1}} and {{qty2}} {{desc2}} {{price2}} {{amount2}},
//    {{subtotal}}, "Tax ({{taxRate}}):" with {{tax}}, and {{total}}.
Dim json As New Chilkat.JsonObject
success = json.UpdateString("placeholders.customer","Acme Corp")
success = json.UpdateString("placeholders.date","2026-10-18")
success = json.UpdateString("placeholders.po","PO-88213")
success = json.UpdateString("placeholders.qty1","2")
success = json.UpdateString("placeholders.desc1","Cordless drill, 18 V")
success = json.UpdateString("placeholders.price1","$460.00")
success = json.UpdateString("placeholders.amount1","$920.00")
success = json.UpdateString("placeholders.qty2","6")
success = json.UpdateString("placeholders.desc2","Galvanized hinge, 4 inch")
success = json.UpdateString("placeholders.price2","$12.50")
success = json.UpdateString("placeholders.amount2","$75.00")
success = json.UpdateString("placeholders.subtotal","$995.00")
success = json.UpdateString("placeholders.taxRate","7.35%")
success = json.UpdateString("placeholders.tax","$73.13")
success = json.UpdateString("placeholders.total","$1,068.13")

//  "apply" makes every replacement, or none: if any value cannot be drawn with the
//  template's font, the method returns false, the PDF is unchanged, and jsonOut says why.
Dim jsonOut As New Chilkat.JsonObject
success = pdf.TextReplace("apply",json,jsonOut)
If (success = False) Then
    System.DebugLog("Not applied: " + jsonOut.Emit())
    If (success = False) Then
        System.DebugLog(pdf.LastErrorText)
        Return
    End If

End If

//  One entry per placeholder: the pages it was found on and how many times it was replaced.
Dim i As Int32
i = 0
Dim count_i As Int32
count_i = jsonOut.SizeOfArray("replacements")
While i < count_i
    jsonOut.I = i
    System.DebugLog(jsonOut.StringOf("replacements[i].field") + ": " + Str(jsonOut.IntOf("replacements[i].count")) + " on page(s) " + jsonOut.StringOf("replacements[i].pages"))
    i = i + 1
Wend

//  The replacements stay in memory until the PDF is written.
success = pdf.WriteFile("qa_output/invoice_filled.pdf")
If (success = False) Then
    System.DebugLog(pdf.LastErrorText)
    Return
End If

System.DebugLog("Wrote qa_output/invoice_filled.pdf")

//  Sample output:

//  customer: 2 on page(s) 1
//  date: 1 on page(s) 1
//  po: 1 on page(s) 1
//  qty1: 1 on page(s) 1
//  desc1: 1 on page(s) 1
//  price1: 1 on page(s) 1
//  amount1: 1 on page(s) 1
//  qty2: 1 on page(s) 1
//  desc2: 1 on page(s) 1
//  price2: 1 on page(s) 1
//  amount2: 1 on page(s) 1
//  subtotal: 1 on page(s) 1
//  taxRate: 1 on page(s) 1
//  tax: 1 on page(s) 1
//  total: 1 on page(s) 1
//  Wrote qa_output/invoice_filled.pdf