IOS开发（75）之把 JSON 数据转化成 Arrays 或者 Dictionaries

1 前言
通过 nsjsonserialization 这个类的 jsonobjectwithdata:options:error:方法来实现，把json 数据解析出来放在数据或者字典里面保存。

2 代码示例
testdemo.m

 

[plain]
-(void)convsefromjson{ 
    nsmutabledictionary *dictionary = [[nsmutabledictionary alloc] init]; 
    [dictionary setvalue:@"anthony" forkey:@"first name"]; 
    [dictionary setvalue:@"robbins" forkey:@"last name"]; 
    [dictionary setvalue:[nsnumber numberwithunsignedinteger:51] forkey:@"age"]; 
    nsarray *arrayofanthonyschildren = [[nsarray alloc] initwithobjects: 
                                        @"anthony's son 1", 
                                        @"anthony's daughter 1", 
                                        @"anthony's son 2", 
                                        @"anthony's son 3", 
                                        @"anthony's daughter 2", nil]; 
    [dictionary setvalue:arrayofanthonyschildren forkey:@"children"]; 
    nserror *error = nil; 
    nsdata *jsondata = [nsjsonserialization 
                        datawithjsonobject:dictionary options:nsjsonwritingprettyprinted error:&error]; 
    if ([jsondata length] > 0 && error == nil){ 
        nslog(@"successfully serialized the dictionary into data."); 
        /* json转数组/字典 */ 
        error = nil; 
        //转换方法 
        id jsonobject = [nsjsonserialization 
                         jsonobjectwithdata:jsondata options:nsjsonreadingallowfragments 
                         error:&error]; 
        if (jsonobject != nil && error == nil){ 
            nslog(@"successfully deserialized..."); 
            //如果jsonobject是字典类 
            if ([jsonobject iskindofclass:[nsdictionary class]]){ 
                nsdictionary *deserializeddictionary = (nsdictionary *)jsonobject; 
                nslog(@"dersialized json dictionary = %@", deserializeddictionary); 
            } 
            //如果jsonobject是数组类 
            else if ([jsonobject iskindofclass:[nsarray class]]){ 
                nsarray *deserializedarray = (nsarray *)jsonobject; 
                nslog(@"dersialized json array = %@", deserializedarray); 
            } else { 
                nslog(@"i can't deal with it"); 
            } 
        } 
        else if (error != nil){ 
            nslog(@"an error happened while deserializing the json data."); } 
    } 
    else if ([jsondata length] == 0 &&error == nil){ 
        nslog(@"no data was returned after serialization."); 
    } 
    else if (error != nil){ 
        nslog(@"an error happened = %@", error); 
    } 
} 

-(void)convsefromjson{
    nsmutabledictionary *dictionary = [[nsmutabledictionary alloc] init];
    [dictionary setvalue:@"anthony" forkey:@"first name"];
    [dictionary setvalue:@"robbins" forkey:@"last name"];
    [dictionary setvalue:[nsnumber numberwithunsignedinteger:51] forkey:@"age"];
    nsarray *arrayofanthonyschildren = [[nsarray alloc] initwithobjects:
                                        @"anthony's son 1",
                                        @"anthony's daughter 1",
                                        @"anthony's son 2",
                                        @"anthony's son 3",
                                        @"anthony's daughter 2", nil];
    [dictionary setvalue:arrayofanthonyschildren forkey:@"children"];
    nserror *error = nil;
    nsdata *jsondata = [nsjsonserialization
                        datawithjsonobject:dictionary options:nsjsonwritingprettyprinted error:&error];
    if ([jsondata length] > 0 && error == nil){
        nslog(@"successfully serialized the dictionary into data.");
        /* json转数组/字典 */
        error = nil;
        //转换方法
        id jsonobject = [nsjsonserialization
                         jsonobjectwithdata:jsondata options:nsjsonreadingallowfragments
                         error:&error];
        if (jsonobject != nil && error == nil){
            nslog(@"successfully deserialized...");
            //如果jsonobject是字典类
            if ([jsonobject iskindofclass:[nsdictionary class]]){
                nsdictionary *deserializeddictionary = (nsdictionary *)jsonobject;
                nslog(@"dersialized json dictionary = %@", deserializeddictionary);
            }
            //如果jsonobject是数组类
            else if ([jsonobject iskindofclass:[nsarray class]]){
                nsarray *deserializedarray = (nsarray *)jsonobject;
                nslog(@"dersialized json array = %@", deserializedarray);
            } else {
                nslog(@"i can't deal with it");
            }
        }
        else if (error != nil){
            nslog(@"an error happened while deserializing the json data."); }
    }
    else if ([jsondata length] == 0 &&error == nil){
        nslog(@"no data was returned after serialization.");
    }
    else if (error != nil){
        nslog(@"an error happened = %@", error);
    }
}
控制台结果

2013-05-13 17:26:15.726 fromjsontest[4944:303] successfully serialized the dictionary into data.

2013-05-13 17:26:15.728 fromjsontest[4944:303] successfully deserialized...

2013-05-13 17:26:15.728 fromjsontest[4944:303] dersialized json dictionary = {

    age = 51;

    "first name" = anthony;

    "last name" = robbins;

    children =     (

        "anthony's son 1",

        "anthony's daughter 1",

        "anthony's son 2",

        "anthony's son 3",

        "anthony's daughter 2"

    );