What is a valid custom format string for boolean data types?

[waltheed]

Hi,
What is a valid custom format string for boolean data types in Power BI?
This property is visible when you use Tabular Editor to manage your datamodel (I mean semantic model :-)). 
In internet posts I see suggestions like "Yes";"Yes";"No" but these do not work. And what do the three options mean? I cannot find any documentation for this. At least not here... Use custom format strings in Power BI Desktop - Power BI | Microsoft Learn

It would be awesome to have this working, so you can do variants like this:
"Has attachment";"Unknown"; "No attachment"
"Overdue";;"In time"

Many thanks. 

[Anonymous]

Hi @waltheed ,

Custom format strings are used to define how data is displayed in Power BI, and when it comes to boolean values, Power BI does not provide direct custom format strings like it does for numeric or date formats. However, you can achieve the desired result by using DAX expressions to convert boolean values into text based on the conditions you specify.

You could  create a measure or a calculated column that displays your custom text for boolean values:

Custom Boolean Format = 
   SWITCH(
      TRUE(),
      [YourBooleanField] = TRUE(), "Yes",  // or "Has attachment", "Overdue", etc.
      [YourBooleanField] = FALSE(), "No",  // or "No attachment", "In time", etc.
      "Unknown"  // This is the default or "else" case
   )

Replace `[YourBooleanField]` with your actual boolean field name.

Best regards,
Community Support Team_Binbin Yu
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