Aniline is treated with excess of ${\mathrm{CH}}_3\mathrm{I}$. The final product is

One mole of ${\text{CH}}_3\mathrm{I}$ reacts with aniline forms N-methylaniline

Two mole of ${\mathrm{CH}}_3\mathrm{I}$ reacts with aniline forms N,N-dimethylaniline

Three mole of ${\mathrm{CH}}_3\mathrm{I}$ reacts with aniline forms N,N,N-trimethyl Anilinium iodide