fieldstr vs fieldnum whats the difference?

Question

Accepted Answer

In Dynamics 365 Finance & Operations (D365 F&O), understanding the difference between fieldNum and fieldStr is key when working with queries in X++, especially when building dynamic ranges.




Feature
fieldNum()
fieldStr()




Returns
Field ID (integer)
Field name (string)


Used For
Used where the system expects a field ID
Used where the system expects a string name of the field


Common Use
QueryBuildDataSource.addRange()
Expressions in queryValue() or complex ranges like FIELD(...)


Example
fieldNum(CustTable, AccountNum) &rarr; 5
fieldStr(CustTable, AccountNum) &rarr; "AccountNum"

Feature	`fieldNum()`	`fieldStr()`
Returns	Field ID (integer)	Field name (string)
Used For	Used where the system expects a field ID	Used where the system expects a string name of the field
Common Use	`QueryBuildDataSource.addRange()`	Expressions in `queryValue()` or complex ranges like `FIELD(...)`
Example	`fieldNum(CustTable, AccountNum)` → `5`	`fieldStr(CustTable, AccountNum)` → `"AccountNum"`

fieldstr vs fieldnum whats the difference?

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