JS up and down key control focus

  This article is mainly about JS key control around the focus of the sample code for a detailed introduction, the need for friends can come to the reference, I hope to help you.

As follows: The following code://begin---------------up and down key control   if (' ${iscontrol_mchntid} '. IndexOf (' ${mchntid} ')!=-1) {  var texts = new Array (); Location var x = 2 set to focus; var y = 3; var maxx = 0; var maxy = 0; Window.onload=function () {var inputs = $ ("[location]"); for (var i = 0; i < inputs.length; i++) {Texts.push (inputs[i)); for (var i = 0; i < texts.length i++) {texts[i].onfocus = new Function ("setcurrent (" + Texts[i].getattribute ("Locati On ") +" ') "); var crtx = parseint (Texts[i].getattribute ("Location"). Split (",") [0]); var crty = parseint (Texts[i].getattribute ("Location"). Split (",") [1]); Maxx = Maxx < Crtx? Crtx:maxx; Maxy = Maxy < Crty? Crty:maxy; Texts[i].onkeydown = function (e) {e = e | | window.event switch (e.keycode) {case 38:setposition (x,y,38); break;//on Case 40 : SetPosition (x,y,40), break;//case 37:setposition (x,y,37), break;//left cases 39:setposition (x,y,39), break;//right 45: SetPosition (x,y,45); Insert key/Return key in the input box is deleted and the input library has a value is deleted other to return to the previous page Default:reTurn true; }}; }}; function SetPosition (x,y,keycode) { //Here Add the dynamic change position logic----begin //up and down, only change y coordinate, x coordinate automatically change/around, only change x coordinate, y coordinate automatically change if (keycode = = ' && x = = ' 3 ') {if (y== ' 3 ') | | y== ' 4 ' | | y== ' 5 ' | | y== ' 6 ' | | y== ' 7 ' | | y== ' 8 ') {y= ' 3 ';}} if (keycode = = ' && x = = ' 4 ') {if (y== ' 3 ') | | y== ' 4 ' | | y== ' 5 ' | | y== ' 6 ' | | y== ' 7 ' | | y== ' 8 ') {y= ' 3 ';}} Add the dynamic change position logic----End   if (keycode = = ' = ') {x =--x; } if (keycode = = ') {x = ++x; } if (keycode = ' 3 7 ') {y =--y; } if (keycode = = ' ") {y = ++y; } moveposition (X,y,keycode); function Moveposition (x1,y1,keycode) {if (keycode = = ' 45 ') {//the cursor is on the object of input var st = x1+ "," +Y1; if ($ ("input[location=" +st+ "']"). attr ("type") = = "text") {var oldval = $ ("input[location= '" +st+ "']"). Val (); var newval = oldval.substring (0, OLDVAL.LENGTH-1); $ ("input[location= '" +st+ "]"). Val (newval); return false; }else{history.go ( -1);  return false;} X1 = x1 > Maxx? 1:x1; y1 = y1 > Maxy? 1:y1; X1 = X1 < 1? maxx:x1; Y1 = y1 < 1? Maxy:y1;   var j = 0; for (; J < Texts.length; J + +) {if (Texts[j].getattribute ("location") = = x1 + "," + y1) {  texts[j].focus (); }  if (j = = texts.length) {switch (keycode) {case 38:moveposition (--x1,y1,keycode); break;//on case 40:moveposition (+ +x1,y1,keycode); break;//case 37:moveposition (x1,--y1,keycode); break;//left Cases 39:moveposition (X1,++y1,keycode); break;//Right}}}  function setcurrent (location) {x = Location.split (",") [0]; y = Location.split (",") [1];}} End---------------up and down key control