tangyangzhe

var guid = function() {
    var S4 = function() {
        return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
    };
    return (S4() + S4() + "-" + S4() + "-" + S4() + "-" + S4() + "-" + S4() + S4() + S4());
};

tangyangzhe

/**
 * Beveled corners — with gradients
 */

div {
	background: #58a;
	background: linear-gradient(135deg, transparent 15px, #58a 0) top left,
	            linear-gradient(-135deg, transparent 15px, #58a 0) top right,
	            linear-gradient(-45deg, transparent 15px, #58a 0) bottom right,
	            linear-gradient(45deg, transparent 15px, #58a 0) bottom left;

tangyangzhe

//**dataURL to blob**
function dataURLtoBlob(dataurl) {
    var arr = dataurl.split(','), mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
    while(n--){
        u8arr[n] = bstr.charCodeAt(n);
    }
    return new Blob([u8arr], {type:mime});
}