String Functions Guide

String manipulation functions for formatting text in your DataMagik document templates.

Table of Contents

1. Case Conversion
2. String Formatting with printf
3. Combining Functions
4. Real-World Examples
5. Best Practices

1. Case Conversion

upper - Convert to Uppercase

{{.Text | upper}}

<h1>{{.CompanyName | upper}}</h1>   <!-- ACME CORPORATION -->
<p>{{.Status | upper}}</p>          <!-- ACTIVE -->
<div>{{.ProductCode | upper}}</div>  <!-- ABC-123 -->

lower - Convert to Lowercase

{{.Text | lower}}

<input type="email" value="{{.Email | lower}}">  <!-- john.doe@example.com -->
<p class="{{.Status | lower}}">{{.Status}}</p>  <!-- class="pending" -->

title - Convert to Title Case

{{.Text | title}}

<h2>{{.FullName | title}}</h2>      <!-- John Doe -->
<p>{{.JobTitle | title}}</p>         <!-- Senior Software Engineer -->

2. String Formatting with printf

The printf function provides C-style string formatting.

Number Formatting

<p>Price: ${{.Price | printf "%.2f"}}</p>          <!-- $1234.50 -->
<p>Percentage: {{.Rate | printf "%.1f"}}%</p>      <!-- 15.8% -->
<p>Precise: {{.Value | printf "%.4f"}}</p>          <!-- 3.1416 -->

Integer Formatting

<p>Quantity: {{.Quantity | printf "%d"}}</p>        <!-- 42 -->
<p>Padded: {{.OrderNumber | printf "%05d"}}</p>    <!-- 00123 -->
<p>Hex: {{.ColorCode | printf "%x"}}</p>            <!-- ff -->

String Formatting

<p>{{.Name | printf "Welcome, %s!"}}</p>           <!-- Welcome, Alice! -->
<p>{{.Code | printf "Code: %10s"}}</p>             <!-- Right-aligned -->

Common printf Format Specifiers

Currency Formatting

<table>
  <tr><td>Subtotal:</td><td>${{.Subtotal | printf "%.2f"}}</td></tr>
  <tr><td>Tax:</td><td>${{.Tax | printf "%.2f"}}</td></tr>
  <tr><td><strong>Total:</strong></td><td><strong>${{.Total | printf "%.2f"}}</strong></td></tr>
</table>

3. Combining Functions

Chain multiple string functions using pipes:

<!-- Convert to lowercase, then title case -->
<p>{{.Name | lower | title}}</p>

<!-- Convert to upper and format -->
<p>{{.Code | upper | printf "Product Code: %s"}}</p>

<!-- Email in lowercase with label -->
<p>{{.Email | lower | printf "Contact: %s"}}</p>

<!-- Status badge with uppercase -->
<span class="badge {{.Status | lower}}">
  {{.Status | upper}}
</span>

4. Real-World Examples

Business Card

<div class="business-card">
  <h2>{{.Name | title}}</h2>
  <p class="title">{{.JobTitle | title}}</p>
  <p>{{.Department | upper}}</p>
  <p>{{.Email | lower}}</p>
  <p>{{.Phone | printf "Tel: %s"}}</p>
</div>

Product Label

<div class="product-label">
  <h1>{{.ProductName | upper}}</h1>
  <p>SKU: {{.SKU | printf "%08d"}}</p>
  <p>Category: {{.Category | title}}</p>
  <p class="price">${{.Price | printf "%.2f"}}</p>
  {{if .OnSale}}
  <p class="sale">Was: ${{.OriginalPrice | printf "%.2f"}}</p>
  <p class="savings">Save: ${{.Savings | printf "%.2f"}}</p>
  {{end}}
</div>

Invoice Line Items

<table>
  <thead>
    <tr><th>Description</th><th>Qty</th><th>Unit Price</th><th>Total</th></tr>
  </thead>
  <tbody>
    {{range .Items}}
    <tr>
      <td>{{.Description | title}}</td>
      <td>{{.Quantity | printf "%d"}}</td>
      <td>${{.UnitPrice | printf "%.2f"}}</td>
      <td>${{.Total | printf "%.2f"}}</td>
    </tr>
    {{end}}
  </tbody>
</table>

Status Badges

{{range .Orders}}
<div class="order">
  <span class="order-id">Order: {{.ID | printf "#%05d"}}</span>
  <span class="badge badge-{{.Status | lower}}">{{.Status | upper}}</span>
</div>
{{end}}

5. Best Practices

• Email Addresses — Always use lower
• Currency — Always use printf "%.2f" for monetary values
• CSS Classes — Use lower for dynamic CSS class names
• IDs and Codes — Use upper for product codes and reference IDs
• Names — Use title for person names and titles
• Consistency — Apply the same formatting rules throughout your template

Function Quick Reference