1. A character inputting method, comprising: when a virtual key in a virtual on-screen keyboard layout is selected by a user, invoking a first probability statistical table matching at least one character having been displayed by at least one virtual key having been selected, wherein the first probability statistical table records combination probabilities of candidate characters respectively being combined with the at least one character; displaying a part of the candidate characters with the highest combination probabilities or all of the candidate characters in the invoked first probability statistical table respectively on virtual keys in the virtual on-screen keyboard layout, and resetting focus on a preset virtual key, wherein in the virtual on-screen keyboard layout, the preset virtual key is configured with the highest level, any of other virtual keys spaced a greater number of steps apart from the preset virtual key is configured with a lower level, the number of steps is the least number of virtual keys along a path from the preset virtual key to the any of other virtual keys, and any of the candidate characters displayed on one of the virtual keys configured with a higher level has higher combination probability; and performing operations above periodically until an ideogram or a character sequence to be input is selected by the user, and inputting the ideogram or the character sequence selected by the user in an input area.