functionup(x,y){//升序返回x[val.prop]-y[val.prop]}functiondown(x,y){//降序返回y[val.prop]-x[val.prop]}arr.sort(up)arr.sort(down)
functionup(x,y){//升序返回x[val.prop]-y[val.prop]}functiondown(x,y){//降序返回y[val.prop]-x[val.prop]}arr.sort(up)arr.sort(down)