nsnumber 转 nsstring

有时候从后台返回数据json转model之后，还是nsnumber 

比如

#import

@interfaceSelectMessageModel :NSObject

/**

*贷款合同号

*/

@property(nonatomic,copy)NSString*contractNo;

/**

*贷款申请序列号

*/

@property(nonatomic,copy)NSString*loanApplySerialNo;

/**

*分期金额

*/

@property(nonatomic,copy)NSString*loanAmount;

/**

*期数

*/

@property(nonatomic,copy)NSString*loanTerm;

/**

*申请时间

*/

@property(nonatomic,copy)NSString*applyTime;

/**

*状态

*/

@property(nonatomic,copy)NSString*applyState;

/*

产品类型

*/

@property(nonatomic,copy)NSString*productType;

- (void)setValue:(id)value forUndefinedKey:(NSString*)key;

但是返回来的loanTerm [model.loanTerm.descriptionstringByAppendingString:@"期"];

这样做就会报错，报nsnumber没有这个方法

这时候

[model.loanTerm.descriptionstringByAppendingString:@"期"];

就好了