What is wrong with this page? Why are all the five pages displayed?

The shoupage is set to 5. Why are all the pages displayed? I changed the shoupage value and displayed all the pages unchanged. {code ...} the shoupage is set to 5. Why are all the pages displayed? I changed the shoupage value and showed that all the pages have not changed.

  "; Echo"
  
  

    "; Echo' 
   
'. $ Page.'/'. $ pagenum.' page |
'; If ($ page = 1) {echo' 
   
Homepage |
'; Echo' 
   
Previous Page |
';} Else {echo' 
   
Homepage |
'; Echo' 
   
Previous Page |
';} If ($ pagenum> $ shoupage) {if ($ page> $ pageoffset) {$ start = $ page-$ pageoffset; $ end = $ pagenum> $ page + $ pageoffset? $ Page + $ pageoffset: $ pagenum;} else {$ start = 1; $ end = $ pagenum> $ shoupage? $ Shoupage: $ pagenum;} if ($ page + $ pageoffset> $ pagenum) {$ start = $ start-($ page + $ pageoffset-$ end);} echo' 
   
'; Echo'
 
   

     '; $ Shoupage = 5; $ pageoffset = ($ shoupage-1)/2; $ start = 1; $ end = $ pagenum; for ($ I = $ start; $ I <= $ end; $ I ++) {echo' 
    
'. ($ I ).'
';} Echo' 
   
'; Echo' 
   
'; If ($ page = $ pagenum) {echo' 
   
| Next page |
'; Echo' 
   
Last page |
';} Else {echo' 
   
| Next page |
'; Echo' 
   
Last page |
';} Echo' 
  
'; Echo'
';};?>

Reply content:

The shoupage is set to 5. Why are all the pages displayed? I changed the shoupage value and showed that all the pages have not changed.

  "; Echo"
  
  

    "; Echo' 
   
'. $ Page.'/'. $ pagenum.' page |
'; If ($ page = 1) {echo' 
   
Homepage |
'; Echo' 
   
Previous Page |
';} Else {echo' 
   
Homepage |
'; Echo' 
   
Previous Page |
';} If ($ pagenum> $ shoupage) {if ($ page> $ pageoffset) {$ start = $ page-$ pageoffset; $ end = $ pagenum> $ page + $ pageoffset? $ Page + $ pageoffset: $ pagenum;} else {$ start = 1; $ end = $ pagenum> $ shoupage? $ Shoupage: $ pagenum;} if ($ page + $ pageoffset> $ pagenum) {$ start = $ start-($ page + $ pageoffset-$ end);} echo' 
   
'; Echo'
 
   

     '; $ Shoupage = 5; $ pageoffset = ($ shoupage-1)/2; $ start = 1; $ end = $ pagenum; for ($ I = $ start; $ I <= $ end; $ I ++) {echo' 
    
'. ($ I ).'
';} Echo' 
   
'; Echo' 
   
'; If ($ page = $ pagenum) {echo' 
   
| Next page |
'; Echo' 
   
Last page |
';} Else {echo' 
   
| Next page |
'; Echo' 
   
Last page |
';} Echo' 
  
'; Echo'
';};?>

@ Eapen he has already said the reason.

Here is a demo I wrote. copy and paste it to run it.

If it is digested, you will learn paging. If you still do not know, please feel free to ask me:

$ Np = @ $ _ GET ['page']; // obtain the current page/** set the number of pages to be displayed. * For example, to display 5 pages * for reasonable display, you need to set an offset: You certainly want to get the offset: (5-1)/2 = 2; ---- "5 6 nowpage 8 9 * What if 6 pages are displayed? * This is not the case (6-1)/2! So you actually need to manually calculate it, as long as you make it into 6 pages: 3 + 1 + 2 = 6 so set: $ offset_forward = 3 $ offset_forward = 2 1 indicates the current page ---> 5 6 7 nowpage 9 10 */$ dp = 12; // how many pages are displayed $ offset_forward = 6; // how many records are shown earlier $ offset_after = 5; // how many days are shown later

/--- Paging function ---/
Function display_data ($ np, $ dp, $ offset_forward, $ offset_after ){

$ Length = 1000; // set the number of records if ($ length = 0) {echo 'No data! ';}$ Total_page = ceil ($ length/$ dp); // calculates the total number of pages. /* --- Limit the number of pages: must be greater than 0 and smaller than the total number of pages --- */if (! Isset ($ np) {$ np = 1;} else {if ($ np <1) {$ np = 1;} if ($ np> $ total_page) {$ np = $ total_page; }}$ btn =""; $ Btn. = "Homepage"; $ btn. = "Previous Page"; if ($ total_page <= $ dp) // if the total number of pages is less than the number of pages to be displayed... {$ start_page = 1; $ end_page = $ total_page; for ($ I = $ start_page; $ I <= $ end_page; ++ $ I) {$ btn. = "$ I" ;}} else {// if the total number of pages is greater than the number of points to be displayed... if ($ np <= $ dp) // if the current page is smaller than or equal to the number of pages to be displayed .. {$ start_page = 1; $ end_page = $ dp; for ($ I = $ start_page; $ I <= $ end_page; ++ $ I) {$ btn. = "$ I" ;}} else {// if the current page is greater than the number of pages to be displayed .. if ($ np + $ offset_forward> $ total_page) // if the offset is added to the current page, it will be greater than the total number of pages .... {$ start_page = $ total_page-$ offset_forward-$ offset_after; $ end_page = $ total_page; for ($ I = $ start_page; $ I <= $ end_page; ++ $ I) {$ btn. = "$ I" ;}} else {// if the current page is added, the offset will be less than the total number of pages .... $ start_page = $ np-$ offset_after; $ end_page = $ np + $ offset_forward; for ($ I = $ start_page; $ I <= $ end_page; ++ $ I) {$ btn. = "$ I" ;}}}$ btn. = "next page"; $ btn. = "last page"; echo $ btn;/* --- add a style to the current page -- */echo <
  

EOT;

} Display_data ($ np, $ dp, $ offset_forward, $ offset_after); // executes the paging Logic

?>

Ah, paging writing is complicated...

If you just want to ask why all of them are displayed

The problem lies in 30 31 rows.

$start=1;$end=$pagenum;

Remove these two rows .. Although there are other problems