项目中常用的JS方法整理_javascript技巧

 function IsImgType(src) {
     var rFilter = /^(?:image\/bmp|image\/cis\-cod|image\/gif|image\/ief|image\/jpeg|image\/jpeg|image\/jpeg|image\/pipeg|image\/png|image\/svg\+xml|image\/tiff|image\/x\-cmu\-raster|image\/x\-cmx|image\/x\-icon|image\/x\-portable\-anymap|image\/x\-portable\-bitmap|image\/x\-portable\-graymap|image\/x\-portable\-pixmap|image\/x\-rgb|image\/x\-xbitmap|image\/x\-xpixmap|image\/x\-xwindowdump)$/i;
     var Filter = /(?:bmp|cis\-cod|gif|ief|jpeg|jpeg|jpeg|pipeg|png|svg\+xml|tiff|x\-cmu\-raster|x\-cmx|x\-icon|x\-portable\-anymap|x\-portable\-bitmap|x\-portable\-graymap|x\-portable\-pixmap|x\-rgb|x\-xbitmap|x\-xpixmap|x\-xwindowdump)$/i;
     return rFilter.test(src) || Filter.test(src);
 }

function detectColor(value) {
    var pattern = /^#[0-9a-fA-F]{6}$/; //#XXXXXX
    var result;
    var rgbRegex = /(^rgb\((\d+),\s*(\d+),\s*(\d+)\)$)|(^rgba\((\d+),\s*(\d+),\s*(\d+)(,\s*\d+\.\d+)*\)$)/;
    if (pattern.test(value)) {
        result = value;
    } else if (rgbRegex.test(value)) { //rgba(0, 0, 0, 0)
        result = value;
    }
    return result;
}

 function zero_fill_hex(num, digits) {
     var s = num.toString(16);
     while (s.length          s = "0" + s;
     }
     return s;
 }
 function rgb2hex(rgb) {
     if (rgb.charAt(0) == '#') {
         return rgb;
     }
     var ds = rgb.split(/\D+/);
     var decimal = Number(ds[1]) * 65536 + Number(ds[2]) * 256 + Number(ds[3]);
     return "#" + zero_fill_hex(decimal, 6);
 }

 function testEmail (value, target) {
     value = value.trim();
     if (!/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(value)) {
         target.val("");
         alert("Please fill in the correct E-mail address!");
     }
 }

function createImgData(img) {
    var image = new Image();
    image.src = img.src || img;
    var tmpCanvas = $("")[0];
    var tmpCtx = tmpCanvas.getContext("2d");
    if (tmpCanvas) {
        tmpCanvas.width = image.width;
        tmpCanvas.height = image.height;
        tmpCtx.drawImage(image, 0, 0);
        return tmpCanvas.toDataURL();
    }
}