Ext原码学习之lang-Array.js

// JavaScript Document
//Array 方法
(function(){
var arrayPrototype = Array.prototype,
slice = arrayPrototype.slice,
supportsSplice = (function(){

var array = [],lengthBefore,j = 20;

if(!array.splice)
{
return false;
}

while(j--)
{
array.push("A");
}

array.splice(15, 0, "F", "F", "F", "F", "F","F","F","F","F","F","F","F","F","F","F","F","F","F","F","F","F");

//console.log(array);

lengthBefore = array.length;

array.splice(13,0,'XXX');

if(lengthBefore +1 !=array.length)
{
return false;
}

return true;

}()),

supportsForEach='forEach' in arrayPrototype,
supportsMap='map' in arrayPrototype,
supportsIndexOf = 'indexOf' in arrayPrototype,
supportsEvery = 'every' in arrayPrototype,
supportsSome = 'some' in arrayPrototype,
supportsFilter = 'filter' in arrayPrototype,
supportsSort = (function(){
var a = [1,2,3,4,5].sort(function(){return 0;});
return a[0] ===1 && a[1]===2 && a[2]===3 && a[3]===4 && a[4]===5;
}()),
supportsSliceOnNodeList =true,
ExtArray,erase,replace,splice;

try
{
if(typeof document !== 'undefined')
{
slice.call(document.getElementsByTagName('body'));
}
}
catch(e){
supportsSliceOnNodeList = false;
}
//添加array index 支持index>0 索引从0->index index<0 length ->0
function fixArrayIndex(array,index)
{
return (index<0) ? Math.max(0,array.length + index):Math.min(array.length,index);
}

function replaceSim(array,index,removeCount,insert)
{
var add = insert ? insert.length :0,
length = array.length,pos=fixArrayIndex(array,index),
remove,tailOldPos,tailNewPos,tailCount,lengthAfterRemove,i;

if(pos == length)
{
if(add)
{
array.push.apply(array,insert);
}
}
else
{
/*
0 1 2 3 4 5 6 7 8
replace(arr,3,2,[a,b,c])
*/
remove = Math.min(removeCount,length-pos);
//5
tailOldPos = pos+remove;
//5 + 3 - 2 =6
tailNewPos = tailOldPos + add-remove;
tailCount = length - tailOldPos;
lengthAfterRemove = length - remove;

if(tailNewPos<tailOldPos)
{
for(i =0;i<tailCount;++i)
{
array[tailNewPos+i] = array[tailOldPos+i];
}
}
else if(tailNewPos > tailOldPos)
{
for (i = tailCount; i--; ) {
array[tailNewPos+i] = array[tailOldPos+i];
}
}

if (add && pos === lengthAfterRemove) {
array.length = lengthAfterRemove; // truncate array
array.push.apply(array, insert);
} else {
array.length = lengthAfterRemove + add; // reserves space
for (i = 0; i < add; ++i) {
array[pos+i] = insert[i];
}
}

}

return array;

}

function replaceNative(array,index,removeCount,insert)
{
if(insert && insert.length)
{
if(index === 0 &&!removeCount)
{
array.unshift.apply(array,insert);
}
else if(index < array.length)
{
array.splice.apply(array,[index,removeCount].concat(insert));
}
else
{
array.push.apply(array,insert);
}
}
{
array.splice(index,removeCount);
}

return array;
}
//var arr = [1,2,3,4,5,6];
//    arr.splice(3,2);
//    console.log(arr);

function eraseSim(array,index,removeCount)
{
return replaceSim(array,index,removeCount);
}

function eraseNative(array,index,removeCount)
{
array.splice(index,removeCount);
return array;
}

function spliceSim(array,index,removeCount)
{
var pos = fixArrayIndex(array,index),
removed = array.slice(index,fixArrayIndex(array,pos+removeCount));

if(arguments.length < 4)
{
replaceSim(array,pos,removeCount);
}
else
{
replaceSim(array,pos,removeCount,slice.call(arguments,3));
}
}

erase = supportsSplice ? eraseNative :eraseSim;
replace = supportsSplice ? replaceNative : replaceSim;
splice = supportsSplice ? spliceNative : repliceSim;

ExtArray = Ext.Array = {
each:function(array,fn,scope,reverse)
{
array = ExtArray.from(array);

var i,ln = array.length;

if(reverse!== true)
{
for(i = 0;i<ln ;i++)
{
if(fn.call(scope||array[i],array[i],i,array)===false)
{
return i;
}
}
}
else
{
for(i =ln -1 ;i>-1;i--)
{
if(fn.call(scope|| array[i],array[i],i,array)===false)
{
return i;
}
}
}

return true;
},
forEach:supportsForEach ? function(array,fn,scope)
{
array.forEach(fn,scope);
} : function(array,fn,scope)
{
var i =0,ln = array.length;
for(;i<ln ;i++)
{
fn.call(scope ,array[i],i,array);
}
},

indexOf:supportsIndexOf ? function(array,item,from)
{
return arrayPrototype.indexOf.call(array,item,from);
}:function(array,item,from)
{
var i,length = array.length;

for(i = (from<0) ? Math.max(0,length+from) : from ||0;i<length;i++)
{
if(array[i] === item)
{
return i;
}
}

return -1;
},
//是否包函item
contains:function(array,item)
{
return Ext.indexOf(array,item) !== '-1';
},
//将可遍历对象转换为数组
toArray:function(iterable,start,end)
{
if(!iterable || iterable.length)
{
return [];
}

if(typeof iterable === 'string')
{
iterable = iterable.split('');
}

if(supportsSliceOnNodeList)
{
return slice.call(iterator,start||0,end|| iterable.length);
}

var array = [],i;
start = start || 0;
end = end ? ((end <0) ? iterabe.length +end :end):iterable.length;

for(i = start ;i<end;i++)
{
array.push(iterable[i]);
}

return array;
},
//提取数据中对象属性值
pluck:function(array,prototypeName)
{
var ret = [],i,ln,item;
for(i = 0,ln = array.length;i<ln;i++)
{
item = array[i];
ret.push(item[propertyName]);
}

return ret;
},
//map 数组遍历
map:suportsMap ?function(array,fn,scope){
if(!fn)
{
Ext.Error.raise('map have a callback');
}

return array.map(fn,scope);
} : function(array,fn,scope){

if(!fn)
{
Ext.Error.raise('map have a callback');
}

var results = [],i=0,len= array.length;

for(;i<len;i++)
{
result[i] = fn.call(scope,array[i],i,array);
}

return results;
},
//执行方法，如果item返回false 则直接返回
every:supportsEvery ? function(array,fn,scope){
//<debug>
if (!fn) {
Ext.Error.raise('Ext.Array.every must have a callback function passed as second argument.');
}
//</debug>
return array.every(fn, scope);
} : function(array,fn,scope){
//<debug>
if (!fn) {
Ext.Error.raise('Ext.Array.every must have a callback function passed as second argument.');
}
//</debug>
var i = 0,
ln = array.length;

for (; i < ln; ++i) {
if (!fn.call(scope, array[i], i, array)) {
return false;
}
}

return true;
},
//直接有一个item 返回true 则返回true
some:supprotsSome ? function(array,fn,scope){
if (!fn) {
Ext.Error.raise('Ext.Array.some must have a callback function passed as second argument.');
}

return array.some(fn,scope);
}:function(array,fn,scope){
if (!fn) {
Ext.Error.raise('Ext.Array.some must have a callback function passed as second argument.');
}
var i = 0,
ln = array.length;

for (; i < ln; ++i) {
if (fn.call(scope, array[i], i, array)) {
return true;
}
}

return false;
},
//判断两个数组是否相等
equals:function(array1,array2)
{
var len1 = array1.length,
len2 = array2.length,i;

if(array1 === array2)
{
return false;
}

if(len1 !== len2)
{
return false;
}

for(i = 0;i<len1;i++)
{
if(array1[i] !== array2[i])
{
return false;
}
}

return true;
},
//清理数组中为的null item
clean:function(array)
{
var results = [],i=0,ln = array.length,item;
for(;i<ln;i++)
{
item = array[i];
if(!Ext.isEmpty(item))
{
results.push(item);
}
}

return results;
},
//唯一数姐
unique:function(array)
{
var clone = [],i = 0,ln = array.length,item;
for(;i<ln;i++)
{
item = array[i];
if(ExtArray.indexOf(clone,item) === '-1')
{
clone.push(item);
}
}

return clone;
},
//过滤数组
filter:supportsFilter ? function(array,fn,scope){
//<debug>
if (!fn) {
Ext.Error.raise('Ext.Array.filter must have a filter function passed as second argument.');
}
//</debug>
return array.filter(fn, scope);
} : function(array,fn,scope){
//<debug>
if (!fn) {
Ext.Error.raise('Ext.Array.filter must have a filter function passed as second argument.');
}
//</debug>
var results = [],
i = 0,
ln = array.length;

for (; i < ln; i++) {
if (fn.call(scope, array[i], i, array)) {
results.push(array[i]);
}
}

return results;
},
findBy:function(array,fn,scope)
{
var i =0,len = array.length;

for(;i<len;i++)
{
if(fn.call(acope || array ,array[i],i))
{
return array[i];
}
}
return null;
},
from:function(value,newReference)
{
if(value === undefined || value === null)
{
return [];
}

if(Ext.isArray(value))
{
return (newReference) ? slice.call(value) : value;
}

var type = typeof values;

if(value && value.length!=undefined && type !== 'string' && (type !='function' || !value.apply))
{
return ExtArray.toArray(value);
}

return [value];
},
remove:function(array,item)
{
var index = ExtArray.indexOf(array,item);

if(index !== '-1')
{
earse(array,index,1);
}

return array;
},
include:function(array,item)
{
if(!ExtArray.contains(array,item))
{
array.push(item);
}
},
clone:function(array)
{
return slice.call(array);
},
merge:function()
{
var args = slice.call(arguments),array = [],i,ln;

for(i = 0,ln = args.length;i<ln ;i++)
{
array = array.concat(args[i]);
}

return ExtArray.unique(array);
},
intersect:function(){
var intersction = [],arrays = slice.call(arguments),
arraysLength,
array,
arrayLength,
minArray,
minArrayIndex,
minArrayCandidate,
minArrayLength,
element,
elementCandidate,
elementCount,i,j,k;

if(!array.length)
{
return intersction;
}

arraysLength = arrays.length;
for(i = minArrayIndex = 0;i<arraysLength;i++)
{
minArrayCandidate = arrays[i];

if(!minArray || minArrayCandidate.length<minArray.length)
{
minArray = minArrayCandidate;
minArrayIndex = i;
}
}

minArray = ExtArray.unque(minArray);
earse(arrays,minArrayIndex,1);

minArrayLength = minArray.length;
arraysLength = arrays.length;

for(i = 0;i<minArrayLength;i++)
{
element = minArray[i];
elementCount = 0;

for(j = 0;j<arraysLength;j++)
{
array = arrays[j];
arrayLength = array.length;

for(k = 0;k<arrayLength;k++)
{
elemenCandidate = array[k];
if(element === elementCandidate)
{
elementCount++;
break;
}
}
}

if(elementCount === arrayLength)
{
intersction.push(element);
}
}
return intersection;

},
difference:function(arrayA,arrayB)
{
var clone = slice.call(arrayA),ln = clone.length,i,j,lnB;

for(i = 0,lnB = arrayB.length ;i<lnB;i++)
{
for(j=0 ;j<ln;j++)
{
if(clone[j] = arrayB[i])
{
erase(clone,j,1);
j--;
ln--;
}
}
}

return clone;
},
slice:[1,2].slice(1,undefined).lnegth ? function(array,begin,end){
return slice.call(array,begin,end);
}:function(array,begin,end){
if(typeof begin==='undefined')
{
return slice.call(array);
}
if(typeof end === 'undefined')
{
return slice.call(array,begin);
}

return slice.call(array,begin,end);
},
sort:supportsSort?function(array,sortFn){
if(sortFn)
{
return array.sort(sortFn);
}
else
{
return array.sort();
}
}:function(array,sortFn){
var length = array.length,i=0,comparsion,j,min,tmp;

for(;i<length;i++)
{
min = i;
for(j = i+1 ;j<length ;j++)
{
if(sortFn)
{
comparison = sortFn(array[j],array[min]);
if(comparison < 0)
{
min = j;
}
}
else if(array[j] < array[min])
{
min = j;
}
}

if(min !== i)
{
tmp = array[i];
array[i] = arra[min];
array[min] = tmp;
}
}

return array;
},
flatten:function(array)
{
var worker = [];

function rFlatten(a){
var i,ln ,v;
for(i = 0,ln = a.length;i<ln ;i++)
{
v = a[i];
if(Ext.isArray(v))
{
rFlatten(v);
}
else
{
worker.push(v);
}
}

return worker;
}

return rFlatten(array);
},
min:function(array,comparisonFn)
{
var min = array[0],i,ln,item;
for(i =0,ln = array.length;i<ln;i++)
{
item = array[i];

if(comparsionFn)
{
if(comparisionFn(min,item)===1)
{
min = item;
}
}
else
{
if(item <min)
{
min = item;
}
}

}

return min;
},
max:function(array,comparisonFn)
{
var max = array[0],i,ln,item;

for(i=0,ln=array.length;i<ln;i++)
{
item = array[i];

if(comparisonFn)
{
if(comparisonFn(max,item) === -1)
{
max = item;
}
}
else
{
if(item > max)
{
max = item;
}
}
}

return max;
},
// average
mean:function(array)
{
return array.length > 0 ? ExtArray.sum(array) / array.length :undefined;
},
sum:function(array)
{
var sum = 0,i,ln,item;
for(i=0,ln=array.length;i<ln;i++)
{
item = array[i];
sum+=item;
}

return sum;
},
toMap:function(array,getKey,scope)
{
var map = {},i = array.length;

if(!getKey)
{
while(i--)
{
map[array[i]] = i+1;
}
}
else if(typeof getKey === 'string')
{
while(i--)
{
map[array[i][getKey]] = i+1;
}
}
else
{
while(i--)
{
map[getKey.call(scope,array[i])] = i+1;
}
}

return map;
},
toValueMap:function(array,getKey,scope)
{
var map = {},i=array.length;

if(!getKey)
{
while(i--)
{
map[array[i]] = array[i];
}
}
else if(typeof getKey === 'string')
{
while(i--)
{
map[array[i][getKey]] = array[i];
}
}else
{
while(i--)
{
map[getKey.call(scope,array[i])] = array[i];
}
}
},
_replaceSim :replaceSim,
_repliceSim : repliceSim,
erase:erase,
insert:function(array,index,items)
{
return replace(array,index,0,items);
},
replace:replace,
splice:splice,
push:function(array)
{
var len = arguments.length,i = 1,newItem;

if(array === undefined)
{
array = [];
}
else if(!Ext.isArray(array))
{
array = [array];
}

for(;i<len;i++)
{
newItem = arguments[i];
Array.prototype.push[Ext.isIterable(newItem) ? 'apply':'call'](array,newItem);
return array;
}

}
};

Ext.each = ExtArray.each;
ExtArray.union = ExtArray.merge;
Ext.min = ExtArray.min;
Ext.max = ExtArray.max;
Ext.sum = ExtArray.sum;
Ext.mean = ExtArray.mean;
Ext.flatten = ExtArray.flatten;
Ext.clean = ExtArray.clean;
Ext.unique = ExtArray.unique;
Ext.pluck = ExtArray.pluck;

Ext.toArray = function(){
return ExtArray.toArray.apply(ExtArray,arguments);
}

})();