Create hex转换成rgba格式 - hex2rgba.js

Rain120 · Apr 2, 2019 · c2e6241 · c2e6241
1 parent 2a315e1
commit c2e6241
Showing 1 changed file with 19 additions and 0 deletions.
diff --git a/hex转换成rgba格式 - hex2rgba.js b/hex转换成rgba格式 - hex2rgba.js
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+/*
+ * hex -> rgba
+ * #ff00ff -> rgba(255, 0, 255, 1)
+ */
+
+function hex2rgba(hex, opacity = 1) {
+  let color;
+  if (/^#([A-Fa-f0-9]{3}){1,2}$/.test(hex)) {
+    color = hex.substring(1).split('');
+    if (color.length === 3) {
+        color= [color[0], color[0], color[1], color[1], color[2], color[2]];
+    }
+    color = '0x' + color.join('');
+    return 'rgba(' + [(color >> 16) & 255, (color >> 8) & 255, color & 255].join(', ') + `, ${opacity})`;
+  }
+  throw new Error('Bad Hex');
+}
+
+hex2rgba('#ef45ae', 0.5);