High-performance Javascript loop Processing

For(VAR I = 0; I <items. length; I ++) {Items [I]. onclicn=FN ;}
 

 
For(I = items. length; I --;) {Items [I]. onclicn=FN ;}
 

 

For(VaRI = 0, Len = items. length; I <ilen; I ++) {Items [I]. onclicn=FN ;}
 

1. One query of attributes of the control condition, such as items. length;

2. Compare the values of one control condition, for example, I <items. length;

3. Compare whether the control condition is true at a time, for example, I <items. Length = true;

4. One auto-increment operation, such as I ++;

5. An array query, such as itmes [I];

6. callback function call, such as items [I]. onclick = FN;

 

The optimization only needs to address the above six aspects...

 

The following figure shows how to expand the (du's device) loop body that is applied to a large number of iterations:

 //  Credit: Jeff Greenberg  VaR I = item. Length % 8 ;  While  (I ){  //  FN (item [I --])  } I = Math. Floor (items. Length/8 );  While  (I ){  //  FN (item [I --]);     // FN (item [I --]);     //  FN (item [I --]);     //  FN (item [I --]);     //  FN (item [I --]);     //  FN (item [I --]);     //  FN (item [I --]);     //  FN (item [I --]); }