19 判断输入是否为数字

//判断是否为整形：

- (BOOL)isPureInt:(NSString*)string{
NSScanner* scan = [NSScanner scannerWithString:string];
int val;
return[scan scanInt:&val] && [scan isAtEnd];
}

//判断是否为浮点形：

- (BOOL)isPureFloat:(NSString*)string{
NSScanner* scan = [NSScanner scannerWithString:string];
float val;
return[scan scanFloat:&val] && [scan isAtEnd];
}    

 if( ![self isPureInt:insertValue.text] || ![self isPureFloat:insertValue.text])
{
    resultLabel.textColor = [UIColor redColor];
    resultLabel.text = @"警告:含非法字符，请输入纯数字！";
    return;
}