# Validity test for a shapefile **URL:** \ **Category:** Uncategorized\ **Created:** [January 7, 2021, 1:49am UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858 "2021-01-07T01:49:41Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![lang](https://avatars.discourse-cdn.com/v4/letter/l/0ea827/32.png) [@lang](https://mapwindow.discourse.group/u/lang)\ **Post date:** [January 7, 2021, 1:49am UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/1 "2021-01-07T01:49:41Z")
Hi, Is there a simple and reliable way (or code) to test if a shapefile is valid? Thanks! ---
**Author:** ![jerryfaust](https://yyz2.discourse-cdn.com/free1/user_avatar/mapwindow.discourse.group/jerryfaust/32/378_2.png) [@jerryfaust](https://mapwindow.discourse.group/u/jerryfaust)\ **Post date:** [January 7, 2021, 6:06pm UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/2 "2021-01-07T18:06:36Z")
Hello @lang There is a [validation call](https://www.mapwindow.org/documentation/mapwingis4.9/group __shapefile__ validation.html) for the Shapes in a Shapefile. Unless you are looking for something higher level. Regards, Jerry. ---
**Author:** ![lang](https://avatars.discourse-cdn.com/v4/letter/l/0ea827/32.png) [@lang](https://mapwindow.discourse.group/u/lang)\ **Post date:** [January 7, 2021, 6:09pm UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/3 "2021-01-07T18:09:53Z")
Jerry, Thanks a lot for the quick response! This is helpful, yet do we have anything higher level? ---
**Author:** ![lang](https://avatars.discourse-cdn.com/v4/letter/l/0ea827/32.png) [@lang](https://mapwindow.discourse.group/u/lang)\ **Post date:** [January 8, 2021, 8:18pm UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/4 "2021-01-08T20:18:29Z")
Jerry, Methods with built-in shapefile validation includes Shapefile.SaveAs, does it mean if a shapefile is saved successfully by using SaveAs, it is valid? Thanks! ---
**Author:** ![lang](https://avatars.discourse-cdn.com/v4/letter/l/0ea827/32.png) [@lang](https://mapwindow.discourse.group/u/lang)\ **Post date:** [January 8, 2021, 8:25pm UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/5 "2021-01-08T20:25:30Z")
Also, what is the easiest way to check is a file is a shapefile? ---
**Author:** ![jerryfaust](https://yyz2.discourse-cdn.com/free1/user_avatar/mapwindow.discourse.group/jerryfaust/32/378_2.png) [@jerryfaust](https://mapwindow.discourse.group/u/jerryfaust)\ **Post date:** [January 9, 2021, 6:14am UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/6 "2021-01-09T06:14:34Z")
Hello @lang It is probably true in general that if you have a Shapefile already in memory, it is a valid Shapefile. Now that doesn’t mean all shapes within that file are valid. So the first test is if you can successfully open a file as a Shapefile, then that’s probably the easiest way to know that it’s a Shapefile. You can then call [FixupShapes](https://www.mapwindow.org/documentation/mapwingis4.9/group __shapefile__ geoprocessing.html#ga196e63e19402ef16992fbe99c049d872), which will check the validity of each of the shapes within the file (there is also a Utils function of the same name). And like you say, when you call SaveAs (which is often called on an in-memory Shapefile), it makes a call to validate the shapes prior to saving. Note that this function will also be creating a DBF file that had not yet existed, and will truncate field names to 10 characters, among other things. (In-memory Shapefiles can have Field names longer than 10 characters). Regards, Jerry. ---
**Author:** ![lang](https://avatars.discourse-cdn.com/v4/letter/l/0ea827/32.png) [@lang](https://mapwindow.discourse.group/u/lang)\ **Post date:** [January 11, 2021, 4:13am UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/7 "2021-01-11T04:13:52Z")
Jerry, Appreciate it! Really helpful. So when I use Shapefile.FixupShapes, it’ll return true when all shape is fixed. it’ll create a new shapefile in memory and I don’t need to save it, right? So just check if returns true, the shapefile is good. This is the first time I know that a dbf is created by SaveAs function. Thanks a lot! lang ---
**Author:** ![pmeems](https://yyz2.discourse-cdn.com/free1/user_avatar/mapwindow.discourse.group/pmeems/32/9_2.png) [@pmeems](https://mapwindow.discourse.group/u/pmeems)\ **Post date:** [January 5, 2022, 10:50am UTC](https://mapwindow.discourse.group/t/validity-test-for-a-shapefile/858/8 "2022-01-05T10:50:16Z")
Just for reference. Use [Shapefile.HasInvalidShapes()](https://mapwindow.org/documentation/mapwingis4.9/group __shapefile__ validation.html#ga1b21d3ace037490c895b0d37b7785511) to first check if you have invalid shapes. This method will stop processing at the first invalid shape, making it faster when used on shapefiles with a lot of shapes. When this method returns true you can call [Shapefile.FixUpShapes()](https://mapwindow.org/documentation/mapwingis4.9/group __shapefile__ geoprocessing.html#ga196e63e19402ef16992fbe99c049d872)