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**ISUPPER(**// string //**)**

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| **ISUPPER** | Returns whether the //string// passed to it contains an upper case alphabetic character. |
| //string// | The label of the string to test. If the //string// contains more than one character, only the first character is tested. |

The ISUPPER procedure returns TRUE if the //string// passed to it is an upper case letter and false otherwise. This is independent of the language and collation sequence. This procedure requires that CLACASE has been set in the application's environment file or through the LOCALE statement.

| **Return Data Type:** | LONG |

**Example:**

**SomeString STRING(1)**

** CODE   **

** SomeString = 'A'         !ISUPPER returns true**

** IF ****ISUPPER****(SomeString) **

**  X#= MESSAGE('Upper case string')**

** END**

** SomeString = 'a'         !ISUPPER returns false**

** IF ****ISUPPER****(SomeString) **

**  X#= MESSAGE('Upper case string')**

** ELSE**

**  X#= MESSAGE('Not upper case string')**

** END**

**See Also:**

[[islower  return lower case character .htm|ISLOWER]]

[[isalpha  return alphabetic character .htm|ISALPHA]]

[[locale  load environment file .htm|LOCALE]]

[[internationalization.htm|Environment Files]]