JavaScript与ActiveX之间传递数据---连载三

本文研究如何在JS等脚本语言与ActiveX控件之间通信，如何传递各种类型的参数，以及COM的IDispatch接口。使用类似的方法，可以推广到其他所有脚本型语言，如LUA，AutoCad等。

本文将研究以下几个方面:

1.         整形数组传参

2.         字符串参数，字符串返回值

3.         修改传入字符串内容

4.         数组参数

5.         IDispatch接口介绍

6.         修改输入数组内容

7.         增加数组内容

8.         以数组传参方式，JS调用S4Execute( )

 

由于本文篇幅较长,所以将以连载方式进行发表,连载一主要讨论1-3点,连载二主要讨论4-6点,连载三主要讨论7-8点.

（七）增加数组内容

1.      在COM中无法向JS中一样，直接增加数组元素。只能使用属性、方法的方式访问数组对象，并以此产生增加数组元素的效果。

2.       JS的Array中包含push( )、 pop( )两个方法，用于在数组尾部增减元素。在COM中需要增减元素时，可通过IDispatch:: Invoke( )接口调用 "push"、"pop"方法来实现。

3.       COM中C++定义

STDMETHODIMP CJsAtl::AddNewElement(VARIANT vArray)

{

         AddArrayElement(vArray.pdispVal, 123);   // 增加元素，值为 123

         return S_OK;

}

 

// ****************************************************

// 向js数组中增加元素

// ****************************************************

HRESULT AddArrayElement(IDispatch* pDisp, int value)

{

         HRESULT hr = 0;

         DISPID      dispid[2] = {0};

         CComBSTR funcName(L"push");

        

         hr = pDisp->GetIDsOfNames(IID_NULL, &funcName, 1, LOCALE_USER_DEFAULT, dispid);

         if (FAILED(hr))

                   return hr;

 

         DISPID dispidNamed = DISPID_UNKNOWN;

         DISPPARAMS params;

         params.rgdispidNamedArgs = NULL;

         params.cArgs = 1;

         params.cNamedArgs = 0;

         params.rgvarg = new VARIANTARG[1];

         params.rgvarg[0].vt = VT_I4;

         params.rgvarg[0].intVal = value;

 

        hr = pDisp->Invoke(dispid[0], IID_NULL, LOCALE_SYSTEM_DEFAULT, DISPATCH_METHOD, &params, NULL, NULL, NULL);        

 

         return hr;

}

4.         JS调用

function test_add_element()

{

       var array = new Array(0, 1, 2, 3);

       try {

              var obj = document.getElementByIdx_x("obj");

              obj.AddNewElement(array);

              alert("length: [" + array.length + "] " + array[array.length - 1]);

       } catch (e) {

              alert("JS ERROR: " + e.message);

       }

}

5.         测试执行

原数组：{0,1,2,3}

增加后：{0,1,2,3,123}

 

（八）以数组传参方式，JS调用S4Execute( )

1.         本例展示如何在JS中执行精锐4锁内程序，且以数组方式处理参数。

2.         本例在Execute传参时，直接以整形数组表示字节数组，而不再需要Hex字符串形式，使得JS端接口更加直观。

3.         JS代码

       var obj = document.getElementByIdx_x("obj");

       var deviceID = "123";

       var userPin = "12345678";

       var fileID  = "0001";

       var inBuff      = new Array(1, 2, 3, 4);

       var outBuff = new Array(0, 0, 0, 0);

       var ret = 0;

       try {

              ret = obj.OpenLock(deviceID);

              ret = obj.ChangeDir("\");

              ret = obj.VerifyPin(userPin);

              ret = obj.Execute(fileID, inBuff, outBuff);

              ret = obj.Close();

       } catch (e) {

              alert("JS Exception: " + e.message);

       }

      

       // JS数组操作，打印结果

       var str = "";

       for (var i = 0; i < outBuff.length; i++)

              str += " " + outBuff[i];

       alert(str);

 

4.          ActiveX代码

SENSE4_CONTEXT  g_ctx = {0}; //全局变量保存当前打开的ctx

 

// 打开设备，以设备ID作为筛选条件，若设备ID指定为空串，则打开第一把锁

STDMETHODIMP CS4ActiveX::OpenLock(BSTR deviceID, LONG* retVal)

{

         SENSE4_CONTEXT *         pctx  =       NULL;

         unsigned long                ret              =       0;

         unsigned long                size   =       0;

         unsigned long                devCount= 0;

         unsigned long                i                  =       0;

         char                               bDeviceID[9]      = {0};

         char                               bUserPin[9]                  = {0};

 

         S4Enum(NULL, &size);

         if (size == 0)

         {

                   *retVal = S4_NO_LIST;

                   goto cleanup;

         }

         pctx = (SENSE4_CONTEXT*) malloc(size);

         ret = S4Enum(pctx, &size);

         if (ret != S4_SUCCESS)

         {

                   *retVal = ret;

                   goto cleanup;

         }

 

         // 获取ascii格式的设备ID

         WideCharToMultiByte(CP_ACP, 0, deviceID, SysStringLen(deviceID), bDeviceID, 9, NULL, NULL);

         // 遍历，寻找deviceID为指定值的设备

         devCount = size / sizeof(SENSE4_CONTEXT);

         for (i = 0; i < devCount; i++)

         {

                   if (strlen(bDeviceID) == 0) // 未指定设备ID，返回第一把锁

                   {

                            break;

                   }

                   if (0 == memcmp(bDeviceID, pctx[i].bID, 8))

                   {

                            break;

                   }

         }

         // 没有找到

         if (i == devCount)

         {

                   *retVal = S4_NO_LIST;

                   goto cleanup;

         }

        

         memcpy(&g_ctx, &pctx[i], sizeof(SENSE4_CONTEXT));

 

         ret = S4Open(&g_ctx);

         if (ret != S4_SUCCESS)

         {

                   *retVal = ret;

                   goto cleanup;

         }

 

         *retVal = S4_SUCCESS;

cleanup:

         if (pctx)

         {

                   free(pctx);

                   pctx = NULL;

         }

         return S_OK;

}

 

STDMETHODIMP CS4ActiveX::ChangeDir(BSTR dir, LONG* retVal)

{

         char            bDir[20]     = {0};

 

         WideCharToMultiByte(CP_ACP, 0, dir, SysStringLen(dir), bDir, 20, NULL, NULL);

         *retVal = S4ChangeDir(&g_ctx, bDir);

         return S_OK;

}

 

STDMETHODIMP CS4ActiveX::Execute(BSTR fileID, VARIANT inBuff, VARIANT outBuf, LONG* retVal)

{

         char            bFileID[5]  =       {0};

         BYTE *               bInBuff               =       NULL;

         BYTE *               bOutBuff   =       NULL;

         int                        inBuffSize  =       0;

         int                        outBuffSize =     0;

         unsigned long size                  =       0;

         unsigned long ret          =       0;

         int                        i                           =       0;

         int                        tmp                     =       0;

 

         GetArrayLength(inBuff.pdispVal, &inBuffSize);

         GetArrayLength(outBuf.pdispVal, &outBuffSize);

 

         if (inBuffSize > 0)

                   bInBuff = (BYTE*) malloc(inBuffSize);

         if (outBuffSize > 0)

                   bOutBuff = (BYTE*) malloc(outBuffSize);

 

         for (i = 0; i < inBuffSize; i++)

         {

                   GetArrayNumberOfIndex(inBuff.pdispVal, i, &tmp);

                   bInBuff[i] = (BYTE)tmp;

         }

 

         WideCharToMultiByte(CP_ACP, 0, fileID, SysStringLen(fileID), bFileID, 5, NULL, NULL);

         ret = S4Execute(&g_ctx, bFileID, bInBuff, inBuffSize, bOutBuff, outBuffSize, &size);

         if (ret != S4_SUCCESS)

         {

                   *retVal = ret;

                   return S_FALSE;

         }

 

         for (i = 0; i < size; i++)

         {

                   SetArrayNumberOfIndex(outBuf.pdispVal, i, bOutBuff[i]);

         }

       

         return S_OK;

}

 

STDMETHODIMP CS4ActiveX::VerifyPin(BSTR userPin, LONG* retVal)

{

         unsigned char      bUserPin[9] = {0};

         WideCharToMultiByte(CP_ACP, 0, userPin, SysStringLen(userPin), (char*)bUserPin, 9, NULL, NULL);

         *retVal = S4VerifyPin(&g_ctx, bUserPin, 8, S4_USER_PIN);

         return S_OK;

}

 

STDMETHODIMP CS4ActiveX::Close(LONG* retVal)

{

         *retVal = S4Close(&g_ctx);

         return S_OK;

}

至此,本篇博文连载完成,希望您通过阅读此系列博文后,可以了解如何在JavaScript以及Acticex之间相互传递数据的问题,当然,也希望您与我们进行互动,能够在此基础之上,再发掘出更好的方法!!!