Question

我正在尝试使用Javascript和SVG以编程方式创建一个圆角。角创建成功，但是path始终设置为0宽度和0高度。

如果我复制创建的字符串元素并将其粘贴到文件中，则它可以正常工作，如代码段第二行所示。

为什么只有以编程方式创建的路径没有宽度和高度？我想念什么？

var cornerTopLeft = createCorner("top-left");
applyCornerStyles.call(cornerTopLeft, 0, 0, 10);

var body = document.getElementsByTagName("body")[0];
body.appendChild(cornerTopLeft);

function createCorner(cornerPosition) {
  var corner = document.createElement("svg");
  corner.setAttribute("fill", "red");
  corner.setAttribute("style", "width:10px;height:10px;background-color: red;");
  corner.setAttribute("viewBox", "0 0 100 100");
  corner.setAttribute("xmlns", "http://www.w3.org/2000/svg")
  corner.innerHTML = '<path class="" style="background-color: rgba(0, 0, 0, .5);fill: rgba(0, 0, 0, .5);" d="M100 0 ,Q 0 0 0 100, L0 0, Z"></path>';
  return corner;
}

function applyCornerStyles(top, left, size) {
  this.style.top = top + "px";
  this.style.left = left + "px";
  this.style.width = size + "px";
  this.style.height = size + "px";
  this.style.zIndex = "20002";
  this.style.position = "absolute";
}

<h3>This svg was created using svg string created programatcally.</h3>
<svg fill="none" viewbox="0 0 100 100" xmlns="http://www.w3.org/2000/svg" style="top: 22px; left: 510px; width: 10px; height: 10px; z-index: 20001; position: absolute;">
  <path class="" style="background-color: rgba(0, 0, 0, .5);fill: rgba(0, 0, 0, .5);" d="M100 0 ,Q 0 0 0 100, L0 0, Z"></path>
</svg>

（fiddle）

Answer 1

使用var corner = document.createElementNS("http://www.w3.org/2000/svg", "svg");代替var corner = document.createElement("svg");

Answer 2

要创建新的svg元素，您需要使用document.createElementNS而不是document.createElement。 ~~此外，您还需要使用document.createElementNS创建路径。 corner.innerHTML = '<path class=...不会。~~

const SVG_NS = 'http://www.w3.org/2000/svg';

var cornerTopLeft = createCorner("top-left");
applyCornerStyles.call(cornerTopLeft, 0, 0, 10);

var body = document.getElementsByTagName("body")[0];
body.appendChild(cornerTopLeft);

function createCorner(cornerPosition) {
  var corner = document.createElementNS(SVG_NS, 'svg');
  corner.setAttributeNS(null,"fill", "red");
  corner.setAttribute("class","corner")
  corner.setAttributeNS(null,"viewBox", "0 0 100 100");
  //corner.setAttribute("xmlns", "http://www.w3.org/2000/svg")
  var path = document.createElementNS(SVG_NS, 'path');
  path.setAttributeNS(null,"fill", "rgba(0, 0, 0, .5)");
  path.setAttributeNS(null,"d","M100 0 ,Q 0 0 0 100, L0 0, Z");
  corner.appendChild(path)
  return corner;
}




function applyCornerStyles(top, left, size) {
  this.style.top = top + "px";
  this.style.left = left + "px";
  this.style.width = size + "px";
  this.style.height = size + "px";
  
  this.style.position = "absolute";
}

svg{border:1px solid}

.corner{background-color: red;}

<h3>This svg was created using svg string created programatcally.</h3>
<svg fill="none" viewbox="0 0 100 100" xmlns="http://www.w3.org/2000/svg" style="top: 22px; left: 510px; width: 10px; height: 10px; z-index: 20001; position: absolute;">
  <path class="" style="background-color: rgba(0, 0, 0, .5);fill: rgba(0, 0, 0, .5);" d="M100 0 ,Q 0 0 0 100, L0 0, Z"></path>
</svg>

用Javascript创建的SVG路径没有宽度或高度

2 个答案: