如何顯示在標籤的字符串值，如果值是零和若干

Question

我JSON對象是這樣的。

 { 
     "id": "1", 
     "subTotal": "20000.00", 
     "total": "124565.00", 
     "timeOfTrans": "3555525", 
     "status": "1", 
     "name": "gjgjgf", 
     "email": "a@a.com", 
     "level": "gjfgj", 
     "teamId": "1" 
    }, 
    { 
     "id": "2", 
     "subTotal": null, 
     "total": null, 
     "timeOfTrans": null, 
     "status": null, 
     "name": "Rajendra", 
     "email": "b@b.com", 
     "level": "gfjgfjg", 
     "teamId": "1" 
    } 

我想在標籤中顯示JSON字符串 「總」。當「總數」爲空時，我想顯示'0'時，「總數」是我想要顯示在同一標籤中的數字的一些數字。

這裏我真的嘗試這種代碼

totalLbl=(UILabel *)[cell viewWithTag:1]; 
id total = [currentEmplyCellDit objectForKey:@"total"]; 
if ([total isKindOfClass:(id)[NSNull null]]) 
{ 
    //Your value of total is NULL 
    totalLbl.text = @"0"; 
} 
//Show the Value. 
totalLbl.text = [NSString stringWithFormat:@"%@",total]; 

驗證碼正確顯示，但我顯示空的標籤時，「總」爲空。

我想顯示0時， 「總」 是NULL

如何解決這個... 感謝。

Answer 1

可以使病情檢查字符串中的空，然後用任何你想要替換此。

id yourValue=[youJSONDict objectForKey:@"total"];; 
if ([yourValue isKindOfClass:[NSNull class]]) { 
    yourLabel.text=@"0"; 
} 
else{ 
    yourLabel.text=[NSString stringWithFormat:@"%@",yourValue]; 
} 

Answer 2

試試這個：

if([dictionary valueForKey:@"total"] != nil) { 
     // The key existed.. 
} 
else { 
     // No joy... 
} 

記住這件事 ：

objectForKey will return nil if a key doesn't exist 


    Symbol Value   Meaning 
    ======= ============= ========================================= 
    NULL  (void *)0  literal null value for C pointers 
    nil  (id)0   literal null value for Objective-C objects 
    Nil  (Class)0  literal null value for Objective-C classes 
    NSNull [NSNull null] singleton object used to represent null 

，看到我的回答Checking a null value from Json response in Objective-C

Answer 3

使用字典或數組只需調用這些函數之一無論您從JSON接收到什麼。這些函數將刪除響應中的所有NULL值。

你必須寫他們遞歸調用對方兩種功能。

呼叫這樣的......

 NSMutableDictionary * ResponseDict =(NSMutableDictionary *)[responseString JSONValue]; 
     ResponseDict = [self removeNullFromDictionary:ResponseDict]; 
     NSLog(@"ResponseDict = %@",ResponseDict); 

這是字典的功能。

-(NSMutableDictionary *)removeNullFromDictionary : (NSMutableDictionary *)dict 
{ 

    for (NSString * key in [dict allKeys]) 
    { 
     if ([[dict objectForKey:key] isKindOfClass:[NSNull class]]) 
     { 
      [dict setValue:@"" forKey:key]; 
     } 
     else if ([[dict objectForKey:key] isKindOfClass:[NSMutableDictionary class]]||[[dict objectForKey:key] isKindOfClass:[NSDictionary class]]) 
     { 
      [dict setObject:[self removeNullFromDictionary:[dict objectForKey:key]] forKey:key]; 
     } 
     else if ([[dict objectForKey:key] isKindOfClass:[NSMutableArray class]]||[[dict objectForKey:key] isKindOfClass:[NSArray class]]) 
     { 
      [dict setObject:[self removeNullFromArray:[dict objectForKey:key]] forKey:key]; 
     } 

    } 

    return dict; 
} 

這是數組

-(NSMutableArray *)removeNullFromArray : (NSMutableArray *)arr 
{ 
    for (int cnt = 0; cnt<[arr count]; cnt++) 
    { 
     if ([[arr objectAtIndex:cnt] isKindOfClass:[NSNull class]]) 
     { 
      [arr replaceObjectAtIndex:cnt withObject:@""]; 
     } 
     else if ([[arr objectAtIndex:cnt] isKindOfClass:[NSMutableDictionary class]]||[[arr objectAtIndex:cnt] isKindOfClass:[NSDictionary class]]) 
     { 
      [arr replaceObjectAtIndex:cnt withObject:[self removeNullFromDictionary:(NSMutableDictionary *)[arr objectAtIndex:cnt]]]; 
     } 
     else if ([[arr objectAtIndex:cnt] isKindOfClass:[NSMutableArray class]]||[[arr objectAtIndex:cnt] isKindOfClass:[NSArray class]]) 
     { 
      [arr replaceObjectAtIndex:cnt withObject:[self removeNullFromArray:(NSMutableArray *)[arr objectAtIndex:cnt]]]; 
     } 
    } 
    return arr; 
} 

功能這肯定會幫助你。必須嘗試.....

Answer 4

if([currentEmplyCellDit objectForKey:@"total"] == [NSNull null]) 
{ 
    yourLbl.text=@"0"; 
} 
else 
{ 
    yourLbl.text = [currentEmplyCellDit objectForKey:@"total"] 
}