Mixing
Img.onerror called randomly - SVG string as source
0
I have a routine that takes a canvas context and an SVG string and renders it onto the canvas, that returns a promise that resolves once done.
For whatever reason, it fails in Firefox & Safari(haven't tried in IE), but seems to be the only solution I can get to work all the time in Chrome. I've tried a couple different alternatives:
- convert it to a blob first, run that blob through createObjectURL, set img src to that, draw image on canvas. This works most of the time over HTTP, but over HTTPS it fails the majority of time, but not all the time.
- Convert it to a blob, use file reader to read it as a base64 SVG representation, set img src to the base64, draw image on canvas.
code:
export default (ctx, rawSVG, { width, height }) =>
new Promise((resolve, reject) => {
const img = new Image(width, height);
img.onload = () => {
ctx.drawImage(img, 0, 0);
resolve(img);
};
img.onerror = err => reject(err);
img.src = `data:image/svg+xml;utf8,${encodeURIComponent(rawSVG)}`;
});
javascript image svg base64
asked Nov 19 '18 at 15:43
Dave
1,41421426
add a comment |
0
I have a routine that takes a canvas context and an SVG string and renders it onto the canvas, that returns a promise that resolves once done.
For whatever reason, it fails in Firefox & Safari(haven't tried in IE), but seems to be the only solution I can get to work all the time in Chrome. I've tried a couple different alternatives:
- convert it to a blob first, run that blob through createObjectURL, set img src to that, draw image on canvas. This works most of the time over HTTP, but over HTTPS it fails the majority of time, but not all the time.
- Convert it to a blob, use file reader to read it as a base64 SVG representation, set img src to the base64, draw image on canvas.
code:
export default (ctx, rawSVG, { width, height }) =>
new Promise((resolve, reject) => {
const img = new Image(width, height);
img.onload = () => {
ctx.drawImage(img, 0, 0);
resolve(img);
};
img.onerror = err => reject(err);
img.src = `data:image/svg+xml;utf8,${encodeURIComponent(rawSVG)}`;
});
javascript image svg base64
asked Nov 19 '18 at 15:43
Dave
1,41421426
Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on theImage()constructor. 2. Try to url-escape the SVG string; an unescaped#will lead to an invalid url.
– ccprog
Nov 19 '18 at 17:05
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
It would probably helpfull to see the source of the SVG (at least the prolog/<svg>tag)
– ccprog
Nov 19 '18 at 19:26
add a comment |
0
0
0
I have a routine that takes a canvas context and an SVG string and renders it onto the canvas, that returns a promise that resolves once done.
For whatever reason, it fails in Firefox & Safari(haven't tried in IE), but seems to be the only solution I can get to work all the time in Chrome. I've tried a couple different alternatives:
- convert it to a blob first, run that blob through createObjectURL, set img src to that, draw image on canvas. This works most of the time over HTTP, but over HTTPS it fails the majority of time, but not all the time.
- Convert it to a blob, use file reader to read it as a base64 SVG representation, set img src to the base64, draw image on canvas.
code:
export default (ctx, rawSVG, { width, height }) =>
new Promise((resolve, reject) => {
const img = new Image(width, height);
img.onload = () => {
ctx.drawImage(img, 0, 0);
resolve(img);
};
img.onerror = err => reject(err);
img.src = `data:image/svg+xml;utf8,${encodeURIComponent(rawSVG)}`;
});
javascript image svg base64
asked Nov 19 '18 at 15:43
Dave
1,41421426
I have a routine that takes a canvas context and an SVG string and renders it onto the canvas, that returns a promise that resolves once done.
For whatever reason, it fails in Firefox & Safari(haven't tried in IE), but seems to be the only solution I can get to work all the time in Chrome. I've tried a couple different alternatives:
- convert it to a blob first, run that blob through createObjectURL, set img src to that, draw image on canvas. This works most of the time over HTTP, but over HTTPS it fails the majority of time, but not all the time.
- Convert it to a blob, use file reader to read it as a base64 SVG representation, set img src to the base64, draw image on canvas.
code:
export default (ctx, rawSVG, { width, height }) =>
new Promise((resolve, reject) => {
const img = new Image(width, height);
img.onload = () => {
ctx.drawImage(img, 0, 0);
resolve(img);
};
img.onerror = err => reject(err);
img.src = `data:image/svg+xml;utf8,${encodeURIComponent(rawSVG)}`;
});
javascript image svg base64
javascript image svg base64
asked Nov 19 '18 at 15:43
Dave
1,41421426
asked Nov 19 '18 at 15:43
Dave
1,41421426
edited Nov 19 '18 at 19:17
asked Nov 19 '18 at 15:43
Dave
1,41421426
asked Nov 19 '18 at 15:43
Dave
1,41421426
asked Nov 19 '18 at 15:43
Dave
1,41421426
1,41421426
Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on theImage()constructor. 2. Try to url-escape the SVG string; an unescaped#will lead to an invalid url.
– ccprog
Nov 19 '18 at 17:05
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
It would probably helpfull to see the source of the SVG (at least the prolog/<svg>tag)
– ccprog
Nov 19 '18 at 19:26
add a comment |
Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on theImage()constructor. 2. Try to url-escape the SVG string; an unescaped#will lead to an invalid url.
– ccprog
Nov 19 '18 at 17:05
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
It would probably helpfull to see the source of the SVG (at least the prolog/<svg>tag)
– ccprog
Nov 19 '18 at 19:26
Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on the
Image() constructor. 2. Try to url-escape the SVG string; an unescaped # will lead to an invalid url.– ccprog
Nov 19 '18 at 17:05
Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on the
Image() constructor. 2. Try to url-escape the SVG string; an unescaped # will lead to an invalid url.– ccprog
Nov 19 '18 at 17:05
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
It would probably helpfull to see the source of the SVG (at least the prolog/
<svg> tag)– ccprog
Nov 19 '18 at 19:26
It would probably helpfull to see the source of the SVG (at least the prolog/
<svg> tag)– ccprog
Nov 19 '18 at 19:26
add a comment |
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Things to check: 1. Depending on the details of your SVG, it might not have an intrinsic size. Try to set explicit width and height parameters on the
Image()constructor. 2. Try to url-escape the SVG string; an unescaped#will lead to an invalid url.– ccprog
Nov 19 '18 at 17:05
Thanks for the suggestions @ccprog, I've made those changes(and updated code example) and Firefox no longer goes into the "onerror" routine, however it doesn't seem to draw the SVG either. Chrome still works.
– Dave
Nov 19 '18 at 19:18
It would probably helpfull to see the source of the SVG (at least the prolog/
<svg>tag)– ccprog
Nov 19 '18 at 19:26