Screen projection method, device and system and storage medium

The embodiment of the invention discloses a screen projection method, device and system and a storage medium. The screen projection method comprises the following steps that the screen projection device receives a text file and/or a control instruction sent by a terminal, and analyzes the text file and/or the control instruction, wherein the terminal and the screen projection device are configuredin the same local area network, and a Client port is arranged in a screen projection applet of the terminal, and a Server port is arranged in the screen projection device, and the terminal and the screen projection device are in communication connection with the Server port through the Client port under the local area network; and the screen projection device adjusts the text file according to the control instruction, and performs screen projection display on the received text file or the adjusted text file. Therefore, rapid and stable real-time screen projection of the text file is realized,and the quality of a scre