1,首先规定一下placeholder的规则
(1)文本框无内容失去焦点时,显示placeher的文字(一般是灰色字体);
(2)文本框聚焦时(还没有输入内容),placeher将消失,即文本框空白
(3)文本框输入内容时,placeholder也消失;
(4)文本框失去焦点时若有内容,则不显示placeholder
2,核心方法
Js代码
- /***
- * convert Decimal str into hex(must be two bit,eg:02,f5)<br>
- * '153'-->99
- * @param str
- */
- to2Hex = function to2Hex(str) {
- var hex = parseInt(str).toString(16);
- if (hex.length === 1) {
- hex = '0' + hex;
- }
- return hex;
- };
- cssColor2Hex = function (cssColor) {
- var stringObj = cssColor.replace(/RGB[\s]*\(([\w,\s]+)\)[\s]*/i, "$1");
- //console.log(stringObj);
- var arr = stringObj.split(',');
- var r = com.whuang.hsj.trim(arr[0]);
- var g = com.whuang.hsj.trim(arr[1]);
- var b = com.whuang.hsj.trim(arr[2]);
- var rHex = to2Hex(r);
- var gHex = to2Hex(g);
- var bHex = to2Hex(b);
- return (rHex + gHex + bHex);
- };
- /***
- *
- * @param hexColor : #ccc
- * @param cssColor : [string]rgb(153, 153, 153)
- * @returns {boolean}
- */
- compareColor = function compareColor(hexColor/*#789*/, cssColor/*rgb(153, 153, 153)*/) {
- if (typeof cssColor !== 'string') {
- return false;
- }
- if (hexColor === cssColor) {//IE8,jquery.css('color') will get '#ddd',but 'rgb(204, 204, 204)'
- return true;
- }
- if (com.whuang.hsj.startsWith(hexColor, '#')) {
- hexColor = hexColor.substr(1);//delete '#' in front
- }
- if (hexColor.length == 3) {
- hexColor = hexColor.substr(0, 1) + hexColor.substr(0, 1)
- + hexColor.substr(1, 1) + hexColor.substr(1, 1) + hexColor.substr(2, 1) + hexColor.substr(2, 1);
- }
- var cssResult = cssColor2Hex(cssColor);
- return (cssResult === hexColor);
- };
