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this method worked out very well, but when I'm using this I found a problem:
in a keyboard press event I use the code:

Expandwith (all){
    // Change the current sprite to its alternate version, if any
    if (ds_map_exists(global.mapSpritesColor, sprite_index))
    {
        sprite_index = ds_map_find_value(global.mapSpritesColor, sprite_index);
    }
    else if (ds_map_exists(global.mapSpritesBW, sprite_index))
    {
        sprite_index = ds_map_find_value(global.mapSpritesBW, sprite_index);
    }
}

but it came out that all of my objects are having a square collision box. It seems that when I'm desaturating the sprites, I also need to copy the original mask information to the new b&w sprites? One method I found is to set every object's mask in the object properties independently, but that's a little complicated and I need some simpler scripts.
I tried this piece of code but it didn't work out:

Expandif mask_index == -1
{
       mask_index = sprite_index;
}

so I guess I totally lost my mask data after sprite_desaturate, is there a method to maintain the mask? Thanks in advance !

can I draw the screen in a black & white style ?
I saw there was a script called sprite_desaturate to desaturate the sprite, it worked out well for sprites. But when I want to desaturate all the instances on the screen, it became really slow to process. So I wonder if I can desaturate the screen instead of desaturate the separate sprites. I tried to play with the code in sprite_desaturate in order to desaturate the screen, but it didn't turn out well (honestly I didn't understand the method in that script ). I revised some of the code in the Begin Step Event:

Expandif (surface_exists(surfScreen)){
    surface_set_target(surfScreen);
    draw_clear_alpha(c_white,1);
    tempsprite = sprite_create_from_surface(surfScreen,0,0,view_wview[0],view_hview[0],0,0,0,0);
    draw_clear_alpha(c_black,1);
    draw_sprite(tempsprite,i,0,0);
    draw_set_blend_mode(bm_add);
    draw_rectangle_color(0,0,view_wview[0],view_hview[0],c_black,c_black,c_black,c_black,false);
    newsprite = sprite_create_from_surface(surfScreen,0,0,view_wview[0],view_hview[0],0,0,0,0);
    draw_sprite(newsprite,-1,0,0);
    surface_reset_target();
    draw_surface(surfScreen,0,0);
//    screen_refresh();
}
else{
    surfScreen = surface_create(view_wview[0], view_hview[0]);
}

but sadly I got nothing. Could you help me with it?

thx for the solution ! I'll try it first

the effect I want to achieve is like this.

one on the left is what actually happens on the screen

the right one is what shows on the screen .

Anyway , I'll try your method first

EDIT: maybe you didn't understand me , and my code is really messy.

what I want to do is draw the whole screen on one surface, and use draw_surface_tiled_ext to fill that surface to the whole screen.

but I don't know how to disable the drawing on screen, without interfering other objects.