js up, down, left and right keys to control focus (sample code)_javascript skills

As shown below:

Copy the code The code is as follows:

//begin-- -------------Up, down, left and right key controls

if('${iscontrol_mchntid}'.indexOf('${mchntid}')!=-1){

var texts = new Array();
//Set to the location where focus is located
var x = 2;
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("location") "')");
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;// Upper
case 40:setPosition(x,y,40);break;// Lower
case 37:setPosition(x,y ,37);break;// Left
case 39:setPosition(x,y,39);break;// Right
case 45:setPosition(x,y,45);break; // Insert key /The return key in the input box is to delete and when the input library has a value, it is to delete, otherwise it is to return to the previous page
default:return true;
}
};
}
};
function setPosition(x,y,keyCode){

//Add the logic of dynamically changing the position here----begin
//When going up and down, only the y coordinate is changed, and the x coordinate changes automatically
//When it is left and right, only the x coordinate and y coordinate are changed Automatically change
if(keyCode == '38' && x == '3'){
if(y=='3'||y=='4'||y=='5'| |y=='6'||y=='7'||y=='8'){
y='3';
}
}
if(keyCode == '40' && x == '4'){
if(y=='3'||y=='4'||y=='5'||y=='6'||y =='7'||y=='8'){
y='3';
}
}
//Add the logic of dynamically changing position here----end

if(keyCode == '38'){
x = --x;
}
if(keyCode == '40'){
x = x;
}
if(keyCode == '37'){
y = --y;
}
if(keyCode == '39'){
y = y;
}
movePosition(x,y,keyCode);
}
function movePosition(x1,y1,keyCode){
if(keyCode == '45'){
//Where the cursor is located When the object is 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();
break;
}
}
if(j == texts.length){
switch(keyCode){
case 38 :movePosition(--x1,y1,keyCode);break;// Upper
case 40:movePosition(x1,y1,keyCode);break;// Lower
case 37:movePosition(x1,--y1 ,keyCode);break;// Left
case 39:movePosition(x1, y1,keyCode);break;// Right
}
}
}
function setCurrent(location){
x = location.split(",")[0];
y = location.split(",")[1];
}
}
//end-- -------------Use up, down, left and right keys to control