在C＃/ .NET中显示来自数据库（While循环）的内容(Display content from Database (While loop) in C# / .NET)

 正如您所说的那样，您没有在参数中使用它们（在调用函数时会出现这种情况），您在创建函数时出现的参数中使用它们。 *和**运算符在每种情况下都有不同的用途。 
 
 在定义函数时，它们指定位置参数将放在元组中，并且关键字参数将放在dict中。 是的我只是说了一些论点，但在这种情况下它们适用于参数。 
 
def example(*args, **kwargs):
    print "args: {0}".format(args)
    print "kwargs: {0}".format(kwargs)

example(1, 2, 'a', foo='bar', bar='foo')
 
 运行时，输出： 
 
args: (1, 2, 'a')
kwargs: {'foo': 'bar', 'bar': 'foo'}
 
 当我说我们将它应用于函数定义中的参数时，你是否明白我的意思？ 参数是1, 2, 'a', foo='bar', bar='foo' 。 参数是*args, **kwargs 。 
 
 现在这里是一个将它们应用于参数的示例。 
 
def example2(a, b, foo=None, bar=None):
    print "a: {0}, b:{1}, foo:{2}, bar: {3}".format(a, b, foo, bar)

args = (1, 2)
kwargs = {'foo': 'bar', 'bar': 'foo'}
example2(*args, **kwargs)
 
 这输出： 
 
a: 1, b:2, foo:bar, bar: foo
 
 你可以看到，当我们将它们应用于参数时（也就是我们调用函数时）， *具有扩展列表或元组以填充函数的位置参数的效果， **具有扩展字典的效果填写函数的关键字参数。 在扩展发生后，您只需要确保总共有足够的参数并且没有太多参数。 
 
 在最后一个例子中，参数是*args, **kwargs ，参数是a, b, foo=None, bar=None 

As you've stated your question, you aren't using them in the arguments (which occur when you are calling a function), you are using them in the parameters which occur when you are creating a function. The * and ** operators serve different purposes in each of those situations.
 
When you are defining a function, they specify that positional arguments will be placed in a tuple and that keyword arguments will be placed in a dict. Yes I did just say arguments, but they are applied to paramaters in this case.
 
def example(*args, **kwargs):
    print "args: {0}".format(args)
    print "kwargs: {0}".format(kwargs)

example(1, 2, 'a', foo='bar', bar='foo')
 
when run, this outputs:
 
args: (1, 2, 'a')
kwargs: {'foo': 'bar', 'bar': 'foo'}
 
Do you see what I mean when I say that we applied it to the paramaters in the function definition? the arguments are 1, 2, 'a', foo='bar', bar='foo'. the paramaters are *args, **kwargs.
 
Now here's an example applying them to arguments.
 
def example2(a, b, foo=None, bar=None):
    print "a: {0}, b:{1}, foo:{2}, bar: {3}".format(a, b, foo, bar)

args = (1, 2)
kwargs = {'foo': 'bar', 'bar': 'foo'}
example2(*args, **kwargs)
 
This outputs:
 
a: 1, b:2, foo:bar, bar: foo
 
You can see that when we apply them to arguments (that is when we are calling the function), * has the effect of expanding a list or tuple to fill the positional arguments of a function and ** has the effect of expanding a dictionary to fill the keyword arguments of a function. You just need to make sure that there are enough and not too much arguments in total after the expansions have taken place.
 
in the last example, the arguments are *args, **kwargs and the parameters are a, b, foo=None, bar=None