A programmable wavelength selective and scanning structure is reported in this paper, which is used to tune the central wavelength of a fiber Bragg grating linearly. Based on such a structure, an all-fiber traveling-wave ring laser is fabricated. The output wavelength can be selected with a computer and can also be continuously scanned in a range of 5.9 nm. The linearity is up to R2=0.999, the wavelength-interval is 0.156 nm, and the wavelength reproducibility is 5.13×10-3 nm, which is within the measuring limit of the optical spectrum analyzer.