21. The method of claim 18 , the GDI document comprises at least a GDI instruction; wherein restoring the received GDI document comprises the steps of performing a graph device function corresponding to the GDI instruction in the GDI document.
21. The method of claim 18 , the GDI document comprises at least a GDI instruction; wherein restoring the received GDI document comprises the steps of performing a graph device function corresponding to the GDI instruction in the GDI document. 22. The method of claim 21 , the method for restoring the received GDI document comprising the steps of: applying, by the network terminal to the document receiver, to its graph device subsystem for a Graph Device Context, reading all the GDI instructions in the received GDI document, sorting all the GDI instructions ascending based on the serial numbers of GDI performance in the GDI instructions, and initializing the variable of the serial number of GDI performance to the minimum of the serial numbers of GDI performance; determining whether the GDI instruction corresponding to the variable of the serial number of GDI performance is found, if the GDI instruction is found, acquiring the number of the GDI function in the current GDI instruction and the GDI function corresponding to the number of the GDI function, performing the GDI function in the Graph Device Context acquired through the application, adding 1 to the variable of the serial number of GDI performance, and cycling back to the step of determining whether the GDI instruction corresponding to the variable of the serial number of GDI performance is found; and if the GDI instruction is not found, determining whether there is a GDI instruction with the serial number of the GDI performance larger than the variable of the serial number of GDI performance, and if there is a GDI instruction with the serial number of the GDI performance larger than the variable of the serial number of GDI performance, adding 1 to the variable of the serial number of GDI performance and cycling back to the step of determining whether the GDI instruction corresponding to the variable of the serial number of GDI performance is found; if there is no GDI instruction with the serial number of the GDI performance larger than the variable of the serial number of GDI performance, closing the GDI document and terminating the procedure for restoring the GDI document.