Question

我使用lcurl将不同的文件（图像，文档，exes等）上传到服务器。文件上传应使用HTTP multipart/formdata完成，curl.easy() :setopt_url(serverUrl) :setopt_httppost(curl.form() :add_file('file', filePath, 'image/png', fName, {'Content-length: ' .. fSize} )) :setopt_postfields('apikey=' .. apikey) :perform() :close()必须包含文件名及其内容。使用lcurl documentation我编写了以下代码（发送图像）：

POST request contains no file field

服务器正在响应#include <opencv2\opencv.hpp> #include <iostream> using namespace std; using namespace cv; vector<vector<Point>> polygons; bool bDraw; vector<Point> poly; Mat3b img; Mat3b layer; Mat3b working; void CallBackFunc(int event, int x, int y, int flags, void* userdata) { if (event == EVENT_LBUTTONDOWN) { //cout << "Left button of the mouse is clicked - position (" << x << ", " << y << ")" << endl; // Refresh working = layer.clone(); if (!bDraw) { // Init your polygon poly.clear(); bDraw = true; } // Add Current Point poly.push_back(Point(x, y)); // Draw Poly for (size_t i = 1; i < poly.size(); ++i) { line(working, poly[i - 1], poly[i], Scalar(0, 255, 0)); } // Draw Points for (size_t i = 0; i < poly.size(); ++i) { circle(working, poly[i], 3, Scalar(0, 0, 255)); } // Update imshow("My Window", working); } else if (event == EVENT_MOUSEMOVE) { //cout << "Mouse move over the window - position (" << x << ", " << y << ")" << endl; // If drawing, update rect width and height if (!bDraw) return; // Refresh working = layer.clone(); // Draw Poly for (size_t i = 1; i < poly.size(); ++i) { line(working, poly[i - 1], poly[i], Scalar(0, 255, 0)); } // Draw Points for (size_t i = 0; i < poly.size(); ++i) { circle(working, poly[i], 3, Scalar(0, 0, 255)); } // Draw Current line line(working, poly.back(), Point(x, y), Scalar(0, 255, 0)); // Update imshow("My Window", working); } else if (event == EVENT_LBUTTONDBLCLK) { //cout << "Left button double clicked" << endl; // Refresh working = layer.clone(); // Add Current Point poly.push_back(Point(x, y)); // Save poly, draw it on layer polygons.push_back(poly); // Draw Poly for (size_t i = 1; i < poly.size(); ++i) { line(working, poly[i - 1], poly[i], Scalar(0, 255, 255)); } // Draw closed poly line(working, poly.back(), poly.front(), Scalar(0, 255, 255)); // Draw Points for (size_t i = 0; i < poly.size(); ++i) { circle(working, poly[i], 3, Scalar(0, 0, 255)); } layer = working.clone(); bDraw = false; // Update imshow("My Window", working); } } int main(int argc, char** argv) { bool bDraw = false; // Read image from file img = imread("path_to_image"); // initialize your temp images layer = img.clone(); working = img.clone(); //if fail to read the image if (img.empty()) { cout << "Error loading the image" << endl; return -1; } //Create a window namedWindow("My Window", 1); //set the callback function for any mouse event setMouseCallback("My Window", CallBackFunc, NULL); //show the image imshow("My Window", working); // Wait until user press 'q' while ((waitKey(1) & 0xFF) != 'q'); // Create cropped images and show / save for (size_t i = 0; i < polygons.size(); ++i) { Mat3b out(img.rows, img.cols, Vec3b(0, 0, 0)); Mat1b mask(img.rows, img.cols, uchar(0)); drawContours(mask, polygons, i, Scalar(255), CV_FILLED); img.copyTo(out, mask); Rect box = boundingRect(polygons[i]); out = out(box).clone(); imshow("Crop #" + to_string(i), out); waitKey(1); //imwrite("Crop #" + to_string(i), out); } waitKey(); return 0; }。

示例代码中哪些不正确？缺少什么？

谢谢！

Answer 1

解决了它。使用:setopt_postfields添加apikey重写file字段。

这是一张运作良好的草图：

curl.easy()
 :setopt_url(url)
 :setopt_httppost(curl.form()
             :add_content('apikey', apikey, 'text/plain')
             :add_file('file', filePath, 'application/octet-stream',
                   fName, {'Content-length: ' .. fSize}
         ))
 :perform()
 :close()

lcurl：使用HTTP multipart / formdata上传文件

1 个答案: