Sharepoint API to create a file

Yes, the SharePoint REST API endpoint you mentioned will overwrite the file if a file with the same name already exists in the specified folder path. The overwrite=true parameter in the URL explicitly instructs SharePoint to replace the existing file with the new one.

Here is the relevant part of the syntax:

https://{site_url}/_api/web/GetFolderByServerRelativeUrl('Folder Name')/Files/add(url='a.txt',overwrite=true)

Parameters:

• url='a.txt': Specifies the name of the file to be created or uploaded.
• overwrite=true: Indicates that if a file with the same name already exists in the specified folder, it should be overwritten.

Behavior:

• If overwrite=true: The existing file with the same name will be replaced by the new file.
• If overwrite=false: An error will be returned if a file with the same name already exists.

Preventing Overwrite:

If you want to prevent overwriting an existing file, you can set overwrite=false. Here’s an example:

POST https://{site_url}/_api/web/GetFolderByServerRelativeUrl('Shared Documents')/Files/add(url='example.txt',overwrite=false)

Authorization: Bearer {access_token}

Accept: application/json;odata=verbose

Content-Type: application/octet-stream

<binary file content>

With overwrite=false, if a file named example.txt already exists in the Shared Documents folder, the request will fail, and you will need to handle that error appropriately.

I have tested the Rest API https://{site_url}/_api/web/GetFolderByServerRelativeUrl('Folder Name')/Files/add(url='a.txt',overwrite=true). When you set parament overwrite=true, the newly created file will override the file with same name already exists.

File created before:

File created new:

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