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**ISSTRING(**// field //**)**

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| **ISSTRING** | Returns true if the //field// is a GROUP, STRING, CSTRING, or PSTRING data type. |
| //field// | The label of a field. |

The **ISSTRING** statement returns true if the //field// is a GROUP, STRING, CSTRING, or PSTRING data type.

| **Return Data Type:** | SIGNED |

**Example:**

**MyGroup  GROUP**

**F1        LONG        !Field number 1**

**F2        SHORT       !Field number 2**

**F3        STRING(30)  !Field number 3**

**InGroup   GROUP       !Field number 3**

**F1         LONG       !Field number 4**

**F2         SHORT      !Field number 5**

**F3         STRING(30) !Field number 6**

**          END**

**         END**

**Flag  LONG**

** CODE**

** Flag = ****ISSTRING****(MyGroup.F1)  !returns FALSE**

** Flag = ****ISSTRING****(MyGroup.F3)  !returns TRUE**

**See Also:**

[[what  return field from group .htm|WHAT]]

[[where  return field position in group .htm|WHERE]]