Concatenate
Joins two strings together into a single string.
Common Properties
- Name - The custom name of the node.
- Color - The custom color of the node.
- Delay Before (sec) - Waits in seconds before executing the node.
- Delay After (sec) - Waits in seconds after executing node.
- Continue On Error - Automation will continue regardless of any error. The default value is false.
If the ContinueOnError property is true, no error is caught when the project is executed, even if a Catch node is used.
Inputs
- First String - The first string to concatenate.
- Second String - The second string to concatenate.
Options
This node does not have configurable options.
Output
- Result - The concatenated string (First String + Second String).
How It Works
The Concatenate node performs simple string concatenation by appending the second string immediately after the first string with no separator or space between them.
If you need to join strings with a separator, use the Join node instead.
Usage Examples
Example 1: Combine Name Parts
Create a full name from first and last name:
- First String:
"John " - Second String:
"Smith" - Result:
"John Smith"
Note: Include the space in the first string since concatenation doesn't add separators.
Example 2: Build File Paths
Combine directory and filename:
- First String:
"/home/user/documents/" - Second String:
"report.pdf" - Result:
"/home/user/documents/report.pdf"
Example 3: Create URLs
Build a complete URL:
- First String:
"https://api.example.com/users/" - Second String:
${msg.userId} - Result:
"https://api.example.com/users/12345"
Example 4: Append File Extensions
Add extension to filename:
- First String:
"invoice_2024_01" - Second String:
".xlsx" - Result:
"invoice_2024_01.xlsx"
Tips
- Include separators in one of the input strings if needed (spaces, slashes, etc.)
- For joining more than two strings, use the Join node with an array
- For complex string building with variables, use the Template node
- Chain multiple Concatenate nodes for joining more than two strings
- Consider using Template node for more readable multi-part string construction
Common Errors and Solutions
Error: Missing spaces between words
- Solution: Include spaces explicitly in your input strings:
"Hello "+"World"="Hello World"
Error: Need to join many strings
- Solution: Use the Join node for arrays of strings, or Template node for complex formatting
Practical RPA Examples
Example: Build Email Subject
First String: "Invoice #"
Second String: ${msg.invoiceNumber}
Result: "Invoice #INV-2024-001"
Example: Construct Database Query
First String: "SELECT * FROM users WHERE email = '"
Second String: ${msg.userEmail} + "'"
Result: "SELECT * FROM users WHERE email = 'user@example.com'"
Be careful with SQL concatenation. Always validate and sanitize inputs to prevent SQL injection.
Example: Create Log Messages
First String: "[ERROR] "
Second String: ${msg.errorMessage}
Result: "[ERROR] Connection timeout"