关于IE8 及以下版本不支持Map() 对象的解决办法
IE8 及以下版本不支持
var map = new Map();
只需要将以下代码拷入中即可。
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function
Map() {
this.
elements =
new
Array();
// 获取Map元素个数
this.
size =
function() {
return
this.
elements.
length;
},
// 判断Map是否为空
this.
isEmpty =
function() {
return (
this.
elements.
length <
1);
},
// 删除Map所有元素
this.
clear =
function() {
this.
elements =
new
Array();
},
// 向Map中增加元素（key, value)
this.
put =
function(
_key,
_value) {
if (
this.
containsKey(
_key) ==
true) {
if (
this.
containsValue(
_value)) {
if (
this.
remove(
_key) ==
true) {
this.
elements.
push({
key :
_key,
value :
_value
});
}
}
else {
this.
elements.
push({
key :
_key,
value :
_value
});
}
}
else {
this.
elements.
push({
key :
_key,
value :
_value
});
}
},
// 向Map中增加元素（key, value)
this.
set =
function(
_key,
_value) {
if (
this.
containsKey(
_key) ==
true) {
if (
this.
containsValue(
_value)) {
if (
this.
remove(
_key) ==
true) {
this.
elements.
push({
key :
_key,
value :
_value
});
}
}
else {
this.
elements.
push({
key :
_key,
value :
_value
});
}
}
else {
this.
elements.
push({
key :
_key,
value :
_value
});
}
},
// 删除指定key的元素，成功返回true，失败返回false
this.
remove =
function(
_key) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
this.
elements.
splice(
i,
1);
return
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 删除指定key的元素，成功返回true，失败返回false
this.
delete =
function(
_key) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
this.
elements.
splice(
i,
1);
return
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 获取指定key的元素值value，失败返回null
this.
get =
function(
_key) {
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
return
this.
elements[
i].
value;
}
}
}
catch (
e) {
return
null;
}
},
// set指定key的元素值value
this.
setValue =
function(
_key,
_value) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
this.
elements[
i].
value =
_value;
return
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 获取指定索引的元素（使用element.key，element.value获取key和value），失败返回null
this.
element =
function(
_index) {
if (
_index <
0 ||
_index >=
this.
elements.
length) {
return
null;
}
return
this.
elements[
_index];
},
// 判断Map中是否含有指定key的元素
this.
containsKey =
function(
_key) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
bln =
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 判断Map中是否含有指定key的元素
this.
has =
function(
_key) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
key ==
_key) {
bln =
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 判断Map中是否含有指定value的元素
this.
containsValue =
function(
_value) {
var
bln =
false;
try {
for (
i =
0;
i <
this.
elements.
length;
i++) {
if (
this.
elements[
i].
value ==
_value) {
bln =
true;
}
}
}
catch (
e) {
bln =
false;
}
return
bln;
},
// 获取Map中所有key的数组（array）
this.
keys =
function() {
var
arr =
new
Array();
for (
i =
0;
i <
this.
elements.
length;
i++) {
arr.
push(
this.
elements[
i].
key);
}
return
arr;
},
// 获取Map中所有value的数组（array）
this.
values =
function() {
var
arr =
new
Array();
for (
i =
0;
i <
this.
elements.
length;
i++) {
arr.
push(
this.
elements[
i].
value);
}
return
arr;
};
/**
* map遍历数组
*
@param
callback
[function] 回调函数；
*
@param
context
[object] 上下文；
*/
this.
forEach =
function
forEach(
callback,
context){
context =
context ||
window;
//IE6-8下自己编写回调函数执行的逻辑
var
newAry =
new
Array();
for(
var
i =
0;
i <
this.
elements.
length;
i++) {
if(
typeof
callback ===
'function') {
var
val =
callback.
call(
context,
this.
elements[
i].
value,
this.
elements[
i].
key,
this.
elements);
newAry.
push(
this.
elements[
i].
value);
}
}
return
newAry;
}
}
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