Block: Join Text

Type: io_text_join

Join two pieces of text into one combined string. Perfect for building dynamic messages, creating formatted outputs, or combining data from different sources into readable text.

What is Join Text?

Think of Join Text like using a plus sign (+) to glue two pieces of text together. Just like "Hello" + "World" becomes "HelloWorld", this block combines any two text values into one.

How It Works

INFO

Input A + Input B → Combined Output

Example: "Hello " + "World" → "Hello World"

The Join Text block takes two inputs (A and B) and combines them into a single text output:

• Input A: First piece of text
• Input B: Second piece of text
• Output: A + B (combined text)

Important!

The texts are joined directly with no space between them. If you want a space, you need to add it yourself!

Basic Examples

Simple Text Joining

Input A	Input B	Output
"Hello"	"World"	"HelloWorld"
"Hello "	"World"	"Hello World"
"Temperature: "	"72°F"	"Temperature: 72°F"

Adding Spaces and Punctuation

Input A	Input B	Output
"Good"	" morning!"	"Good morning!"
"Status:"	" Active"	"Status: Active"
"User"	"#1234"	"User#1234"

IoT Use Cases

🏷️ Creating Labels with Values

Temperature Label:

A: "Kitchen Temp: "
B: {{ feeds['sensors.kitchen_temp'].value }}
// Output: "Kitchen Temp: 72.5"

Device Status:

A: "Door is "
B: {{ feeds['security.door'].value }}
// Output: "Door is OPEN" or "Door is CLOSED"

📊 Building Status Messages

Battery Level:

A: "Battery at "
B: {{ vars.battery_percent }}%
// Output: "Battery at 85%"

Sensor with Units:

A: {{ feeds['sensors.humidity'].value }}
B: "% humidity"
// Output: "65% humidity"

👤 Personalizing Messages

Welcome Message:

A: "Welcome back, "
B: {{ user.name }}
// Output: "Welcome back, John Smith"

Custom Greeting:

A: {{ vars.greeting }}
B: {{ user.username }}
// Output: "Hello, jsmith123"

🔗 Creating URLs and Paths

API Endpoint

A: "https://api.example.com/sensors/"
B: {{ vars.sensor_id }}
// Output: "https://api.example.com/sensors/temp_01"

File Path

A: "/data/"
B: {{ vars.filename }}
// Output: "/data/readings_2024.csv"

🎨 Formatting with Symbols

// Arrow Indicators
A: "Temperature "
B: "↑ Rising"
// Output: "Temperature ↑ Rising"

// Status Icons
A: "🔋 "
B: {{ vars.battery_status }}
// Output: "🔋 Charging" or "🔋 Full"

Advanced Patterns

Chaining Multiple Join Blocks

Sometimes you need to combine more than two pieces of text. Use multiple Join Text blocks:

Three-Part Message:

// First Join
A: "Hello, "
B: {{ user.name }}
// Result: "Hello, John"

// Second Join (using first result)
A: [First Join Output]
B: "! Welcome back."
// Final Output: "Hello, John! Welcome back."

Building Complex Messages

Multi-Line Status Report (using \n for line breaks):

// First Join
A: "System Status\n"
B: "Temperature: OK\n"

// Second Join
A: [First Join]
B: "Humidity: OK\n"

// Third Join
A: [Second Join]
B: "Battery: Low"

/* Output:
System Status
Temperature: OK
Humidity: OK
Battery: Low
*/

Conditional Text Building

Combine with logic blocks to build different messages:

A: "Sensor "
B: [If temperature > 80 then "⚠️ HOT" else "✓ Normal"]
// Output: "Sensor ⚠️ HOT" or "Sensor ✓ Normal"

Common Patterns & Tips

1. Don't Forget Spaces!

Common Mistake

Forgetting to add spaces is the #1 beginner error!

Wrong:

A: "Hello"
B: "World"
// Output: "HelloWorld" ❌

Right:

A: "Hello "  // Space at the end
B: "World"
// Output: "Hello World" ✅

Also Right:

A: "Hello"
B: " World"  // Space at the beginning
// Output: "Hello World" ✅

2. Adding Separators

Separator	Input A	Input B	Output
Comma	{{ vars.city }}	", USA"	"Boston, USA"
Dash	{{ vars.date }}	" - Event"	"2024-01-15 - Event"
Colon	"Error"	": Connection lost"	"Error: Connection lost"

3. Building Lists

// Bullet Point
A: "• "
B: {{ vars.item_name }}
// Output: "• Temperature Sensor"

// Numbered
A: "1. "
B: {{ vars.first_step }}
// Output: "1. Check connections"

4. Combining Numbers and Text

When joining numbers with text, the number is automatically converted:

A: "Count: "
B: {{ vars.sensor_count }}
// Output: "Count: 5"

A: {{ feeds['sensor'].value }}
B: " degrees"
// Output: "72.5 degrees"

5. Empty String Handling

If one input is empty, you get just the other input:

A: "Hello"
B: ""
// Output: "Hello"

A: ""
B: "World"
// Output: "World"

Working with Other Blocks

Join + Text Template

Use Join Text to prepare strings for templates:

// Join to create feed key
A: "sensor."
B: {{ vars.location }}
// Output: "sensor.kitchen"

// Then use in template
{{ feeds['[Join Output]'].value }}

Join + Variables

Store joined text in a variable for reuse:

// Join
A: "Alert: "
B: {{ vars.message }}

// Store result in variable: "formatted_alert"
// Use later in multiple places

Join + Conditionals

Build different messages based on conditions:

A: "Status: "
B: [If block result]
// Where If block returns "Online" or "Offline"
// Output: "Status: Online" or "Status: Offline"

Troubleshooting

Problem: Text runs together without spaces

Solution: Add a space at the end of the first text or beginning of the second text:

• Change "Hello" to "Hello "
• Or change "World" to " World"

Problem: Getting [object Object] in output

Solution: Make sure you're passing text/string values, not complex objects. Use the .value or .name property of feeds:

• Wrong: B: {{ feeds['sensor.temp'] }}
• Right: B: {{ feeds['sensor.temp'].value }}

Problem: Numbers not displaying correctly

Solution: Numbers are automatically converted to text. For formatting, use a Text Template block first:

• Basic: A: "Price: $" B: {{ vars.price }} → "Price: $9.99"
• Formatted: Use template with {{ vars.price | round: 2 }} first

Problem: Special characters not showing

Solution: Use Unicode or HTML entities:

• Degree symbol: Use "°" or "°"
• Line break: Use "\n"
• Tab: Use "\t"

Quick Reference

Task Reference Table

Task	Input A	Input B	Output
Add label	"Temp: "	"72°F"	"Temp: 72°F"
Add units	"50"	"%"	"50%"
Add prefix	"Error: "	message	"Error: [message]"
Add suffix	filename	".txt"	"[filename].txt"
Join names	first_name	last_name	"[first][last]" (no space!)
With space	first_name + " "	last_name	"[first] [last]"
Line break	"Line 1\n"	"Line 2"	Two lines
Build path	"/home/"	username	"/home/[username]"

When to Use Join Text vs Text Template

Use Join Text when:

• Combining exactly two pieces of text
• Simple concatenation without complex formatting
• Building URLs, paths, or IDs
• Adding prefixes or suffixes

Use Text Template when:

• Combining more than two pieces of text
• Need advanced formatting (dates, numbers)
• Using conditional logic
• Creating multi-line messages
• Need more control over output format

Inputs

A

The first string of text - this will appear first in the combined output. Can be static text like 'Hello' or dynamic data from feeds/variables. Don't forget to add a space at the end if you want separation from the second text!

B

The second string of text - this will appear immediately after the first text with no automatic spacing. Can be static text or dynamic values. Add a space at the beginning if you need separation from the first text.