Question

我在python中有这段代码：

"{0}.currentTime += 1;".format(hairSyst)

其中hairSyst是前面定义的字符串。我不明白为什么我会收到语法错误。我的目标是在maya中设置一个表达式，并且表达式有点长，我将整个事情粘贴到下面，也许你可以建议一个更好的方法来做它。

expr = ("if ({0}.autoOverlap == 1){".format(firstControl.getName())
        "{0}.currentTime += 1;".format(hairSyst)
        "{0}.currentTime += 1;".format(nucleus)
        "float $refresh_tx = {0}.translateX;".format(cube)
        "float $refresh_ty = {0}.translateY;".format(cube)
        "float $refresh_tz = {0}.translateZ;".format(cube)
        "float $refresh_rx = {0}.rotateX;".format(cube)
        "float $refresh_ry = {0}.rotateY;".format(cube)
        "float $refresh_rz = {0}.rotateZ;".format(cube)
        "}else if({0}.autoOverlap == 0){".format(firstControl.getName())
        "{0}.currentTime = 1;".format(hairSyst)
        "{0}.currentTime = 1;".format(nucleus)
        "}"
)

Answer 1

最好将其设为format字符串：

expr = """if ({0}.autoOverlap == 1){{
          {1}.currentTime += 1;
          {2}.currentTime += 1;
          float $refresh_tx = {3}.translateX;
          float $refresh_ty = {3}.translateY;
          float $refresh_tz = {3}.translateZ;
          float $refresh_rx = {3}.rotateX;
          float $refresh_ry = {3}.rotateY;
          float $refresh_rz = {3}.rotateZ;
          }}else if({0}.autoOverlap == 0){{"
          {1}.currentTime = 1;
          {2}.currentTime = 1;
          }}""".format(firstControl.getName(), hairSyst, nucleus, cube)

请注意，使用"""三重引号代替"单引号来格式化多行字符串。

编辑：

如果原始字符串包含{ }，我们必须按{{ }}按class LeftExplorerItem : public Component, public MouseListener { public: LeftExplorerItem(String name = "LeftExplorerItem") : Component(name), isActive(false) { setSize(100, 20); addMouseListener(this, true); } void paint(Graphics& g) override { if (!isActive) g.setColour(Colour(40, 40, 40)); else g.setColour(Colour(150, 190, 255)); g.fillRoundedRectangle(2, 2, getWidth() - 4, getHeight() - 4, 4); g.setColour(Colours::white); g.drawText("Frame #", 40, 0, 100, 25, Justification::centredLeft); } void mouseEnter(const MouseEvent& event) override { AlertWindow("", "", AlertWindow::AlertIconType::InfoIcon); isActive = true; } void mouseExit(const MouseEvent& event) override { isActive = false; } void mouseUp(const MouseEvent& event) override { AlertWindow("", "click", AlertWindow::AlertIconType::InfoIcon); } void resized() override { } private: bool isActive; JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(LeftExplorerItem) };转义它们：

6.1.3。格式字符串语法

str.format（）方法和Formatter类共享相同的语法   对于格式字符串（虽然在Formatter的情况下，子类可以   定义自己的格式字符串语法。）

格式字符串包含由大括号括起的“替换字段”   {}。任何未包含在大括号中的内容都被视为文字   文本，未更改地复制到输出。 如果您需要包含   文字文本中的大括号字符，可以通过加倍来逃避：   {{和}}。

Answer 2

你必须连接这些字符串。现在，eval()看到您传入了13个字符串，但eval()只接受了一个字符串。所以做这样的事情：

expr = ("if ({0}.autoOverlap == 1){ ".format(firstControl.getName()) + 
     "{0}.currentTime += 1; ".format(hairSyst) + 
     "{0}.currentTime += 1; ".format(nucleus) + 
     "float $refresh_tx = {0}.translateX; ".format(cube) + 
     "float $refresh_ty = {0}.translateY; ".format(cube) + 
     "float $refresh_tz = {0}.translateZ; ".format(cube) + 
     "float $refresh_rx = {0}.rotateX; ".format(cube) + 
     "float $refresh_ry = {0}.rotateY; ".format(cube) + 
     "float $refresh_rz = {0}.rotateZ; ".format(cube) + 
     "}else if({0}.autoOverlap == 0){ ".format(firstControl.getName()) + 
     "{0}.currentTime = 1; ".format(hairSyst) + 
     "{0}.currentTime = 1; ".format(nucleus) + 
     "}"
)

我还在每个字符串后面添加了空格，以确保它们不会相互碰撞。

格式化字符串SyntaxError

2 个答案: