javascript - 如何将参数传递给 evaluateJavaScript 函数？

Question

for (int i = 0; i < centerPointsList.size (); i++)
    {
        QVariant         holdInformation = map->page ()->mainFrame ()->evaluateJavaScript (QString ("constructFileName (%1).arg (centerPointsList[0].toFloat())"));
        QList <QVariant> allListObj      = holdInformation.toList ();
        QList <QVariant> fileNamesList   = allListObj[0].toList ();

        std :: cout << fileNamesList[0].toFloat() << "================= \n";

    }

这导致:

"SyntaxError: Parse error on line:1 Source:undefined"
Segmentation fault

我猜测错误出在我将列表项传递给函数 evaluateJavaScript 的方式上。

更新:

---

我试过这个:

for (int i = 0; i < centerPointsList.size (); i++)
 {
   QVariant holdInformation = map->page ()->mainFrame ()->evaluateJavaScript (QString ("constructFileName (%1)").arg (centerPointsList [0].toFloat ()));

结果是:

"TypeError: Result of expression 'centerPointFileName.split' [undefined] is not a function. on line:65 Source:file:///.../index.html"

函数constructFileName(Javascript)如下:

function constructFileName (centerPointFileName)
 {
   var removeSpaces = centerPointFileName.split (" ");
   var fileNameWithoutSpaces = "", i;
   for (i = 0; i < removeSpaces.length; i++)
       fileNameWithoutSpaces = fileNameWithoutSpaces + removeSpaces [i];

Answer 1

根据您的更新，您的 JavaScript 函数需要一个字符串参数。最简单的方法应该是这样的:

QString info = QString("constructFileName('%1')").arg(centerPointsList[i].toFloat());
QVariant holdInformation = map->page()->mainFrame()->evaluateJavaScript(info);

但是，一般来说这并不完全安全 - 如果内插参数 %1 包含反斜杠、双引号或其他特殊符号，则需要先对它们进行转义。我无法评论应该如何完成，因为我从未使用过 Qt :)