sysallocstring

sysallocstring 是一个Windows API函数，被用于在Windows环境下分配Unicode字符串的内存空间。它接收一个ANSI字符串作为参数，并将其转换为Unicode字符串，然后在进程的堆中分配一块内存用于存储该字符串，返回一个指向该内存块的指针。这个函数通常在COM编程中使用，因为COM需要使用Unicode字符串。

相关问题

c语言读取excel数据存储在数组里

要在C语言中读取Excel数据并将其存储在数组中，可以使用以下步骤：

1. 包含必要的头文件和库：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <errno.h>
#include <windows.h>
#include <ole2.h>
#include <olectl.h>
#include <ocidl.h>

2. 使用COM接口打开Excel文件，并获取工作簿和工作表对象：

// 打开Excel文件
CoInitialize(NULL);
IDispatch* pXLApp = NULL;
CLSID clsid;
CLSIDFromProgID(L"Excel.Application", &clsid);
HRESULT hr = CoCreateInstance(clsid, NULL, CLSCTX_LOCAL_SERVER, IID_IDispatch, (void**)&pXLApp);
if (FAILED(hr)) {
    printf("Failed to create Excel instance.\n");
    return 1;
}
// 打开工作簿
VARIANT varFileName;
VariantInit(&varFileName);
varFileName.vt = VT_BSTR;
varFileName.bstrVal = SysAllocString(L"example.xlsx"); // Excel文件名
IDispatch* pWorkbooks = NULL;
hr = pXLApp->GetIDispatch(L"Workbooks", (void**)&pWorkbooks);
if (FAILED(hr)) {
    printf("Failed to get Workbooks object.\n");
    return 1;
}
IDispatch* pWorkbook = NULL;
hr = pWorkbooks->Invoke(0x3ec, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
if (FAILED(hr)) {
    printf("Failed to get item(1) of Workbooks object.\n");
    return 1;
}
// 获取工作表对象
VARIANT varWorksheetName;
VariantInit(&varWorksheetName);
varWorksheetName.vt = VT_BSTR;
varWorksheetName.bstrVal = SysAllocString(L"Sheet1"); // 工作表名
IDispatch* pWorksheets = NULL;
hr = pWorkbook->GetIDispatch(L"Worksheets", (void**)&pWorksheets);
if (FAILED(hr)) {
    printf("Failed to get Worksheets object.\n");
    return 1;
}
IDispatch* pWorksheet = NULL;
hr = pWorksheets->Invoke(0x74, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
if (FAILED(hr)) {
    printf("Failed to get Item() of Worksheets object.\n");
    return 1;
}

3. 获取Excel数据的范围，并确定数组的大小：

// 获取数据范围
VARIANT varRangeName;
VariantInit(&varRangeName);
varRangeName.vt = VT_BSTR;
varRangeName.bstrVal = SysAllocString(L"A1:C10"); // 数据范围
IDispatch* pRange = NULL;
hr = pWorksheet->GetIDsOfNames(IID_NULL, &varRangeName.bstrVal, 1, LOCALE_USER_DEFAULT, &dispid);
if (FAILED(hr)) {
    printf("Failed to get IDs of names.\n");
    return 1;
}
hr = pWorksheet->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
if (FAILED(hr)) {
    printf("Failed to get Range object.\n");
    return 1;
}
pRange = varResult.pdispVal;
// 获取数据大小
long numRows = 0;
long numCols = 0;
hr = pRange->GetIDsOfNames(IID_NULL, &dispidNumRows, 1, LOCALE_USER_DEFAULT, &dispid);
if (FAILED(hr)) {
    printf("Failed to get IDs of names.\n");
    return 1;
}
hr = pRange->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
if (FAILED(hr)) {
    printf("Failed to get number of rows.\n");
    return 1;
}
numRows = varResult.lVal;
hr = pRange->GetIDsOfNames(IID_NULL, &dispidNumCols, 1, LOCALE_USER_DEFAULT, &dispid);
if (FAILED(hr)) {
    printf("Failed to get IDs of names.\n");
    return 1;
}
hr = pRange->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
if (FAILED(hr)) {
    printf("Failed to get number of columns.\n");
    return 1;
}
numCols = varResult.lVal;
// 确定数组大小
int numRowsInt = (int)numRows;
int numColsInt = (int)numCols;
double** pData = (double**)malloc(numRowsInt * sizeof(double*));
for (int i = 0; i < numRowsInt; i++) {
    pData[i] = (double*)malloc(numColsInt * sizeof(double));
}

4. 读取数据并存储在数组中：

// 读取数据
for (int i = 1; i <= numRowsInt; i++) {
    for (int j = 1; j <= numColsInt; j++) {
        VARIANT varValue;
        VariantInit(&varValue);
        IDispatch* pCell = NULL;
        hr = pRange->GetIDsOfNames(IID_NULL, &dispidItem, 1, LOCALE_USER_DEFAULT, &dispid);
        if (FAILED(hr)) {
            printf("Failed to get IDs of names.\n");
            return 1;
        }
        VARIANTARG vargIndex;
        VariantInit(&vargIndex);
        vargIndex.vt = VT_I4;
        vargIndex.lVal = i * pow(2, 16) + j;
        dispparams.rgvarg = &vargIndex;
        dispparams.cArgs = 1;
        hr = pRange->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &varResult, NULL, NULL);
        if (FAILED(hr)) {
            printf("Failed to get cell.\n");
            return 1;
        }
        pCell = varResult.pdispVal;
        hr = pCell->GetIDsOfNames(IID_NULL, &dispidValue, 1, LOCALE_USER_DEFAULT, &dispid);
        if (FAILED(hr)) {
            printf("Failed to get IDs of names.\n");
            return 1;
        }
        hr = pCell->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varValue, NULL, NULL);
        if (FAILED(hr)) {
            printf("Failed to get cell value.\n");
            return 1;
        }
        pData[i - 1][j - 1] = varValue.dblVal;
    }
}

5. 关闭Excel文件和COM接口：

// 关闭对象
pRange->Release();
pWorksheet->Release();
pWorksheets->Release();
pWorkbook->Release();
pWorkbooks->Release();
pXLApp->Release();
// 释放内存
for (int i = 0; i < numRowsInt; i++) {
    free(pData[i]);
}
free(pData);
// 关闭COM接口
CoUninitialize();

完整的代码如下所示：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <errno.h>
#include <windows.h>
#include <ole2.h>
#include <olectl.h>
#include <ocidl.h>

int main()
{
    // 打开Excel文件
    CoInitialize(NULL);
    IDispatch* pXLApp = NULL;
    CLSID clsid;
    CLSIDFromProgID(L"Excel.Application", &clsid);
    HRESULT hr = CoCreateInstance(clsid, NULL, CLSCTX_LOCAL_SERVER, IID_IDispatch, (void**)&pXLApp);
    if (FAILED(hr)) {
        printf("Failed to create Excel instance.\n");
        return 1;
    }
    // 打开工作簿
    VARIANT varFileName;
    VariantInit(&varFileName);
    varFileName.vt = VT_BSTR;
    varFileName.bstrVal = SysAllocString(L"example.xlsx"); // Excel文件名
    DISPPARAMS dispparamsNoArgs = { NULL, NULL, 0, 0 };
    VARIANT varResult;
    IDispatch* pWorkbooks = NULL;
    hr = pXLApp->GetIDispatch(L"Workbooks", (void**)&pWorkbooks);
    if (FAILED(hr)) {
        printf("Failed to get Workbooks object.\n");
        return 1;
    }
    DISPID dispid = 0;
    hr = pWorkbooks->GetIDsOfNames(IID_NULL, &L"Open", 1, LOCALE_USER_DEFAULT, &dispid);
    if (FAILED(hr)) {
        printf("Failed to get IDs of names.\n");
        return 1;
    }
    VARIANTARG dispparamsOpen[4];
    dispparamsOpen[3].vt = VT_BOOL;
    dispparamsOpen[3].boolVal = FALSE;
    dispparamsOpen[2].vt = VT_BOOL;
    dispparamsOpen[2].boolVal = FALSE;
    dispparamsOpen[1].vt = VT_BOOL;
    dispparamsOpen[1].boolVal = FALSE;
    dispparamsOpen[0].vt = VT_BSTR;
    dispparamsOpen[0].bstrVal = varFileName.bstrVal;
    dispparams.cArgs = 4;
    dispparams.rgvarg = dispparamsOpen;
    hr = pWorkbooks->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, &dispparams, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to open workbook.\n");
        return 1;
    }
    IDispatch* pWorkbook = NULL;
    hr = pWorkbooks->Invoke(0x3ec, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to get item(1) of Workbooks object.\n");
        return 1;
    }
    pWorkbook = varResult.pdispVal;
    // 获取工作表对象
    VARIANT varWorksheetName;
    VariantInit(&varWorksheetName);
    varWorksheetName.vt = VT_BSTR;
    varWorksheetName.bstrVal = SysAllocString(L"Sheet1"); // 工作表名
    IDispatch* pWorksheets = NULL;
    hr = pWorkbook->GetIDispatch(L"Worksheets", (void**)&pWorksheets);
    if (FAILED(hr)) {
        printf("Failed to get Worksheets object.\n");
        return 1;
    }
    IDispatch* pWorksheet = NULL;
    hr = pWorksheets->Invoke(0x74, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to get Item() of Worksheets object.\n");
        return 1;
    }
    // 获取数据范围
    VARIANT varRangeName;
    VariantInit(&varRangeName);
    varRangeName.vt = VT_BSTR;
    varRangeName.bstrVal = SysAllocString(L"A1:C10"); // 数据范围
    DISPID dispidNumRows = 0;
    DISPID dispidNumCols = 0;
    DISPID dispidItem = 0;
    DISPID dispidValue = 0;
    IDispatch* pRange = NULL;
    hr = pWorksheet->GetIDsOfNames(IID_NULL, &varRangeName.bstrVal, 1, LOCALE_USER_DEFAULT, &dispid);
    if (FAILED(hr)) {
        printf("Failed to get IDs of names.\n");
        return 1;
    }
    hr = pWorksheet->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to get Range object.\n");
        return 1;
    }
    pRange = varResult.pdispVal;
    // 获取数据大小
    long numRows = 0;
    long numCols = 0;
    hr = pRange->GetIDsOfNames(IID_NULL, &L"Rows", 1, LOCALE_USER_DEFAULT, &dispidNumRows);
    if (FAILED(hr)) {
        printf("Failed to get IDs of names.\n");
        return 1;
    }
    hr = pRange->Invoke(dispidNumRows, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to get number of rows.\n");
        return 1;
    }
    numRows = varResult.lVal;
    hr = pRange->GetIDsOfNames(IID_NULL, &L"Columns", 1, LOCALE_USER_DEFAULT, &dispidNumCols);
    if (FAILED(hr)) {
        printf("Failed to get IDs of names.\n");
        return 1;
    }
    hr = pRange->Invoke(dispidNumCols, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varResult, NULL, NULL);
    if (FAILED(hr)) {
        printf("Failed to get number of columns.\n");
        return 1;
    }
    numCols = varResult.lVal;
    // 确定数组大小
    int numRowsInt = (int)numRows;
    int numColsInt = (int)numCols;
    double** pData = (double**)malloc(numRowsInt * sizeof(double*));
    for (int i = 0; i < numRowsInt; i++) {
        pData[i] = (double*)malloc(numColsInt * sizeof(double));
    }
    // 读取数据
    for (int i = 1; i <= numRowsInt; i++) {
        for (int j = 1; j <= numColsInt; j++) {
            VARIANT varValue;
            VariantInit(&varValue);
            IDispatch* pCell = NULL;
            hr = pRange->GetIDsOfNames(IID_NULL, &L"Item", 1, LOCALE_USER_DEFAULT, &dispid);
            if (FAILED(hr)) {
                printf("Failed to get IDs of names.\n");
                return 1;
            }
            VARIANTARG dispparamsItem[1];
            dispparamsItem[0].vt = VT_I4;
            dispparamsItem[0].lVal = i * pow(2, 16) + j;
            DISPPARAMS dispparams = { dispparamsItem, NULL, 1, 0 };
            hr = pRange->Invoke(dispid, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparams, &varResult, NULL, NULL);
            if (FAILED(hr)) {
                printf("Failed to get cell.\n");
                return 1;
            }
            pCell = varResult.pdispVal;
            hr = pCell->GetIDsOfNames(IID_NULL, &L"Value", 1, LOCALE_USER_DEFAULT, &dispidValue);
            if (FAILED(hr)) {
                printf("Failed to get IDs of names.\n");
                return 1;
            }
            hr = pCell->Invoke(dispidValue, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET, &dispparamsNoArgs, &varValue, NULL, NULL);
            if (FAILED(hr)) {
                printf("Failed to get cell value.\n");
                return 1;
            }
            pData[i - 1][j - 1] = varValue.dblVal;
        }
    }
    // 关闭对象
    pRange->Release();
    pWorksheet->Release();
    pWorksheets->Release();
    pWorkbook->Release();
    pWorkbooks->Release();
    pXLApp->Release();
    // 释放内存
    for (int i = 0; i < numRowsInt; i++) {
        free(pData[i]);
    }
    free(pData);
    // 关闭COM接口
    CoUninitialize();
    return 0;
}

c++调用stk生成轨道数据的代码

STK（Systems Tool Kit）提供了COM接口，可以通过C++调用STK生成轨道数据。具体步骤如下：

1. 安装STK软件并打开STK。
2. 在STK中创建一个场景，添加卫星、星座等对象，并设置其属性。
3. 在STK中生成轨道数据文件（.e文件），并保存到本地磁盘。
4. 在C++中通过COM接口调用STK，读取轨道数据文件并进行处理。

下面是一个简单的示例代码，演示了如何通过COM接口调用STK并生成轨道数据：

// C++代码
#include <iostream>
#include <windows.h>
#include <oleauto.h>

int main()
{
    // 初始化COM接口
    CoInitialize(NULL);

    // 创建STK对象
    IDispatch* pStkApp;
    CLSID clsid;
    CoCreateInstance(CLSID_Application, NULL, CLSCTX_SERVER, IID_IDispatch, (void**)&pStkApp);

    // 打开STK场景文件
    VARIANT result;
    BSTR filePath = SysAllocString(L"C:\\Temp\\MyScene.e");
    VARIANT vtFilepath;
    vtFilepath.vt = VT_BSTR;
    vtFilepath.bstrVal = filePath;
    DISPID dispID;
    DISPPARAMS dispParams = { NULL, NULL, 0, 0 };
    pStkApp->GetIDsOfNames(IID_NULL, &filePath, 1, LOCALE_USER_DEFAULT, &dispID);
    pStkApp->Invoke(dispID, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, &dispParams, &result, NULL, NULL);

    // 生成轨道数据
    VARIANT objPath;
    objPath.vt = VT_BSTR;
    objPath.bstrVal = SysAllocString(L"Satellite1");
    VARIANT vtStartTime;
    vtStartTime.vt = VT_BSTR;
    vtStartTime.bstrVal = SysAllocString(L"01 Jan 2022 00:00:00.000");
    VARIANT vtStopTime;
    vtStopTime.vt = VT_BSTR;
    vtStopTime.bstrVal = SysAllocString(L"01 Jan 2023 00:00:00.000");
    VARIANT vtInterval;
    vtInterval.vt = VT_BSTR;
    vtInterval.bstrVal = SysAllocString(L"60");
    VARIANT vtFilePath;
    vtFilePath.vt = VT_BSTR;
    vtFilePath.bstrVal = SysAllocString(L"C:\\Temp\\MyOutputFile.txt");
    VARIANT vtFormat;
    vtFormat.vt = VT_BSTR;
    vtFormat.bstrVal = SysAllocString(L"e");
    VARIANT vtCmd;
    vtCmd.vt = VT_BSTR;
    vtCmd.bstrVal = SysAllocString(L"ExportData");
    DISPPARAMS exportParams = { &objPath, &vtStartTime, &vtStopTime, &vtInterval, &vtFilePath, &vtFormat, 7, 0 };
    pStkApp->GetIDsOfNames(IID_NULL, &vtCmd.bstrVal, 1, LOCALE_USER_DEFAULT, &dispID);
    pStkApp->Invoke(dispID, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, &exportParams, &result, NULL, NULL);

    // 释放资源
    SysFreeString(filePath);
    SysFreeString(objPath.bstrVal);
    SysFreeString(vtStartTime.bstrVal);
    SysFreeString(vtStopTime.bstrVal);
    SysFreeString(vtInterval.bstrVal);
    SysFreeString(vtFilePath.bstrVal);
    SysFreeString(vtFormat.bstrVal);
    SysFreeString(vtCmd.bstrVal);
    pStkApp->Release();
    CoUninitialize();

    return 0;
}

需要注意的是，由于STK是Windows平台下的软件，因此该代码只能在Windows操作系统上运行。