当C++遇到IOS应用开发之---List集合

在Object-c中，数组使用NSArray和NSMutableArray(可变长数组)。使用语法如下：
[cpp]
NSArray *array = [[NSArray alloc] initWithObjects:@"One",@"Two",@"Three",@"Four",nil];

取数组元素的方法:
[html]
[array objectAtIndex:2]);

因为数组在开发中会被频繁使用，且objectAtIndex的写法看着过于繁复，远不如array[2]这种直观。所以我将C++中的vector类进行了封装，并增加一些新的功能：www.2cto.com

[cpp]
#include
#include

using namespace std;
using namespace std::tr1;
template >
class List: public vector
{
private:
typedef typename std::vector::iterator list_it;

list_it _it;

public:
List(){}

List(NSArray *array){
copyFromArray(array);
}


List(string *array){
copyFromArray(array);
}

List(int *array){
copyFromArray(array);
}

~List()
{
std::cout<<"list destroy!"< }

List& add(const T t){
this->push_back(t);
return (*this);
}

void clear(){
//this->clear();
this->erase(this->begin(), this->end());
}


BOOL contains(const T t){
return indexOf(t) >= 0;
}


int indexOf(const T t){
list_it it = std::find(this->begin(),this->end() , t ) ;
if(it != this->end())
return it - this->begin();
return -1 ;
}

void insert(int index, const T t)
{
this->insert(this.begin() + index, 1, t);
}


void remove(const T t)
{
int pos = indexOf(t);
if (pos >= 0)
this->removeAt(pos);
}

void removeAt(int index)
{
if (this->size() > index){
this->erase(this->begin() + index, this->begin() + index + 1);
}
}

int count()
{
return this->size();
}

void copyFrom(List list)
{
this->assign(list.begin(), list.end());
}

void copyFromArray(NSArray *array){
for(int i = 0; i< [array count]; i++){
T t = (T)[array objectAtIndex:i];
this->push_back(t);
}
}

void copyFromArray(string* array){
for(int i = 0; i< array->length(); i++){
T t = (T)array[i];
this->push_back(t);
}
}

void copyFromArray(int* array){
for(int i = 0; i<(sizeof(array)/sizeof(int)); i++){
T t = (T)array[i];
this->push_back(t);
//this->vector::push_back(new T);//usage:用父类方法 或 static_cast*>(this)->push_back(T);
}
}
};

用法如下

实例化对象并添加数据：
[cpp]
List list;
list.add(@"1");
list.add(@"2代震军");
list.add(@"333").add(@"44444").add(@"5");

或用下面方式：
[cpp]
NSArray *array = [[NSArray alloc] initWithObjects:
@"One",@"Two",@"Three",@"Four",nil];
List list1(array);

判断是否存在某数据：
[cpp]
NSString *del = @"44444";
bool iscontains = list.contains(del);

删除数据：
[cpp]
list.removeAt(2);
list.remove(del);

遍历：
[cpp]
for(List::iterator it = list.begin() ;it != list.end() ; it++)
cout << [(*it) UTF8String ]<<" " ;

或使用foreach:
[cpp]
__block NSString* str;
for_each(list.begin(), list.end(), ^(NSString *value){
str = value;
std::cout<<[value UTF8String]< });

获取指定索引记录:
[cpp]
NSString * result = list[0];