Indicates the check characters corresponding to the current barcode data.
public char getCheckChars()
Most barcode types have no or one check character; few have two.
Just like barcode data, depending on the barcode type, a check character may not have the corresponding ASCII code. When this is the case, the character returned will have 128 added to the original native character code, suggesting a native code, not ASCII; you need to subtract 128 from it to get the actual native character code.