Data URI scheme详解和使用实例及图片base64编码实现

data:image/gif;base64,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

data:,文本数据
data:text/plain,文本数据
data:text/html,HTML代码
data:text/html;base64,base64编码的HTML代码
data:text/css,CSS代码
data:text/css;base64,base64编码的CSS代码
data:text/javascript,Javascript代码
data:text/javascript;base64,base64编码的Javascript代码
data:image/gif;base64,base64编码的gif图片数据
data:image/png;base64,base64编码的png图片数据
data:image/jpeg;base64,base64编码的jpeg图片数据
data:image/x-icon;base64,base64编码的icon图片数据
base64简单地说，它把一些 8-bit 数据翻译成标准 ASCII 字符，在PHP中可以用函数base64_encode() 进行编码。

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<img src=“data:image/gif;base64,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”/>

function readFile(){
var file = this.files[0];
if(!/image///w+/.test(file.type)){
alert("请确保文件为图像类型");
return false;
}
var reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = function(e){
result.innerHTML = '<img src="'+this.result+'" alt=""/>';
img_area.innerHTML = '<div class="sitetip">图片img标签展示：</div><img src="'+this.result+'" alt=""/>';
}
}

function readFile(){
var file = this.files[0];
if(!/image///w+/.test(file.type)){
alert("请确保文件为图像类型");
return false;
}
var reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = function(e){
result.innerHTML = '<img src="'+this.result+'" alt=""/>';
img_area.innerHTML = '<div class="sitetip">图片img标签展示：</div><img src="'+this.result+'" alt=""/>';
}
}