php怎么调用.NET开发的webservice

php如何调用.NET开发的webservice
接口地址是：http://pi.f3.cn/F3WebService.asmx

要调用的方法是：

SendSMS 
短信发送 

大家看看短信接口应该怎么写？我老是调用不成功

我先说明下我的代码：

PHP code

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<?php class SendSMSParam
{    
    public $ToUserText; 
    public $ToUserByte; 
    public $SMSContent;
    public $PlanSendTime;
    public $MSGType; 
    public $LongCode;
}

class SendSMS
{
    public $SMSParam;
    public $ECECCID;
    public $Password;
}

$userid=1234567;//接入账户
$pwd="abcdefg";//接入密码
$mobile="13800000000";//下发手机号
$content="php测试短信";
$client=new SoapClient("http://pi.f3.cn/F3WebService.asmx?WSDL");
$SMSParam = new SendSMSParam();
$SMSParam->ToUserText=$mobile;
$SMSParam->SMSContent=$content;
$SMSParam->MSGType=5;
$SendSMSinfo=new SendSMS();
$SendSMSinfo->SMSParam=$SMSParam;
$SendSMSinfo->ECECCID=$userid;
$SendSMSinfo->Password=$pwd;
print_r($SendSMSinfo);
$client->SendSMS($SendSMSinfo);
?>

------解决方案--------------------
Fatal error: Uncaught SoapFault exception: [soap:Client] 服务器无法读取请求。 ---> XML 文档(2, 268)中有错误。 ---> 字符串“”不是有效的 AllXsd 值。 in
.....php:34 Stack trace: #0
.....php(34): SoapClient->__call('SendSMS', Array) #1 
.....php(34): SoapClient->SendSMS(Object(SendSMS)) #2
------解决方案--------------------

C/C++ code

<element minoccurs="0" maxoccurs="1" name="SMSParam" type="tns:SendSMSParam"></element>
<element minoccurs="1" maxoccurs="1" name="ECECCID" type="s:long"></element>
<element minoccurs="0" maxoccurs="1" name="Password" type="s:string"></element>

<complextype name="SendSMSParam">
<sequence>
<element minoccurs="0" maxoccurs="1" name="ToUserText" type="s:string"></element>
<element minoccurs="0" maxoccurs="1" name="ToUserByte" type="s:base64Binary"></element>
<element minoccurs="0" maxoccurs="1" name="SMSContent" type="s:string"></element>
<element minoccurs="1" maxoccurs="1" name="PlanSendTime" type="s:dateTime"></element>
<element minoccurs="1" maxoccurs="1" name="MSGType" type="tns:c"></element>
<element minoccurs="0" maxoccurs="1" name="LongCode" type="s:string"></element>
</sequence>
</complextype>

<simpletype name="MSGType">
<restriction base="s:string">
<enumeration value="NoSMS"></enumeration>
<enumeration value="ShortSMS"></enumeration>
<enumeration value="LongSMSNoPageNum"></enumeration>
<enumeration value="LongSMSWithPageNum"></enumeration>
<enumeration value="LongSMS"></enumeration>
<enumeration value="WAPPush"></enumeration>
<enumeration value="MMS"></enumeration>
<enumeration value="NMS"></enumeration>
</restriction>
</simpletype> <div class="clear">
                 
              
              
        
            </div>