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**VLBProc( **//rowindex//**, **//colindex //**), VIRTUAL, PROTECTED**

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| **VLBProc** | Retrieve LIST and error history information. |
| //rowindex// | An index used to determine information regarding the listbox and associated history data. |
| //colindex// | An index used to determine information regarding an actual error history record. |

The **VLBProc **method returns various information regarding the LIST control and its data.

**Implementation:**

If passed a //rowindex //of -1, the VLBProc returns the number of history error records that are contained in the error history queue. If passed a rowindex of -2, the method returns the number of listbox columns.

Any positive integer passed as the rowindex will cause the VLBProc to lookup the error history record at the relative rowindex position. The //colindex// parameter is used in association with a positive integer rowindex. A colindex value of 1 will return the error text. A colindex of 2 will return the error category.

**Return Data Type:**     STRING