Django初体验（一）:自定义表单提交
注：本人使用的Django1.8.3版本进行测试
除了使用Django内置表单，有时往往我们需要自定义表单。对于自定义表单Post方式提交往往会带来由CSRF(跨站请求伪造)产生的错误"CSRF verification failed. Request aborted."
本篇博客只要针对"表单提交"和"Ajax提交"两种方式来解决CSRF带来的错误
一、表单提交
Template：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>计算数字和</title>
</head>
<body>
<form method="post" action="{%url 'Calculate' %}">
{% csrf_token %}
<label for="A"><input id="A" name="ValueA" type="text"></label>
<label for="B"><input id="B" name="ValueB" type="text"></label>
<input type="submit" value="开始计算">
</form>
</body>
</html>
Views.py:
def Calculate(request):
if request.POST:
a=request.POST["ValueA"]
b=request.POST["ValueB"]
c=str(int(a)+int(b))
return render_to_response('Result.html',{'result':c})
else:
return render_to_response('Calculation.html',context_instance=RequestContext(request))
需要注意：
(1)在<form>标签内添加{% csrf_token %},这样在表单提交的过程中，会产生"csrfmiddlewaretoken"标识去防止CSRF
(2)在Get请求页面时，需要添加context_instance=RequestContext(request) ,它和{% csrf_token %}配合使用，缺少一个都会出现上述错误,RequestContext 需要在 django.shortcuts 导入
(3)只有当表单以Post方式提交时，才需要验证CSRF，Get方式是不需要的
二、Ajax提交
同比与表单提交，Ajax提交需要进行额外的操作，Ajax提交时需要自己提供"csrfmiddlewaretoken"标识参数。我们除了需要引入JQuery外还需要引入一段JS代码
jQuery(document).ajaxSend(function(event, xhr, settings) {
function getCookie(name) {
var cookieValue = null;
if (document.cookie && document.cookie != '') {
var cookies = document.cookie.split(';');
for (var i = 0; i < cookies.length; i++) {
var cookie = jQuery.trim(cookies[i]);
// Does this cookie string begin with the name we want?
if (cookie.substring(0, name.length + 1) == (name + '=')) {
cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
break;
}
}
}
return cookieValue;
}
function sameOrigin(url) {
// url could be relative or scheme relative or absolute
var host = document.location.host; // host + port
var protocol = document.location.protocol;
var sr_origin = '//' + host;
var origin = protocol + sr_origin;
// Allow absolute or scheme relative URLs to same origin
return (url == origin || url.slice(0, origin.length + 1) == origin + '/') ||
(url == sr_origin || url.slice(0, sr_origin.length + 1) == sr_origin + '/') ||
// or any other URL that isn't scheme relative or absolute i.e relative.
!(/^(\/\/|http:|https:).*/.test(url));
}
function safeMethod(method) {
return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method));
}
if (!safeMethod(settings.type) && sameOrigin(settings.url)) {
xhr.setRequestHeader("X-CSRFToken", getCookie('csrftoken'));
}
});
Template：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Ajax 提交</title>
<script type="text/javascript" src="/static/jquery.js"></script>
<script type="text/javascript">
jQuery(document).ajaxSend(function(event, xhr, settings) {
function getCookie(name) {
var cookieValue = null;
if (document.cookie && document.cookie != '') {
var cookies = document.cookie.split(';');
for (var i = 0; i < cookies.length; i++) {
var cookie = jQuery.trim(cookies[i]);
// Does this cookie string begin with the name we want?
if (cookie.substring(0, name.length + 1) == (name + '=')) {
cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
break;
}
}
}
return cookieValue;
}
function sameOrigin(url) {
// url could be relative or scheme relative or absolute
var host = document.location.host; // host + port
var protocol = document.location.protocol;
var sr_origin = '//' + host;
var origin = protocol + sr_origin;
// Allow absolute or scheme relative URLs to same origin
return (url == origin || url.slice(0, origin.length + 1) == origin + '/') ||
(url == sr_origin || url.slice(0, sr_origin.length + 1) == sr_origin + '/') ||
// or any other URL that isn't scheme relative or absolute i.e relative.
!(/^(\/\/|http:|https:).*/.test(url));
}
function safeMethod(method) {
return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method));
}
if (!safeMethod(settings.type) && sameOrigin(settings.url)) {
xhr.setRequestHeader("X-CSRFToken", getCookie('csrftoken'));
}
});
</script>
<script type="text/javascript">
$(function(){
$.ajaxSetup({
data:{csrfmiddlewaretoken: '{{ csrf_token }}'}
});
$("#Comment").click(function(){
$.post('{% url 'AjaxRequest' %}',{"a":$("#A").val(),"b":$("#B").val()},function(data){
$("#result").html(data);
});
});
});
</script>
</head>
<body>
<label for="A"><input id="A" name="ValueA" type="text"></label>
<label for="B"><input id="B" name="ValueB" type="text"></label>
<input type="button" id="Comment" value="开始计算">
<h1>计算的结果为：<span id="result"></span></h1>
</body>
</html>
View.py：
def AjaxRequest(request):
if request.POST:
a =request.POST["a"]
b=request.POST["b"]
c=int(a)+int(b)
return JsonResponse(c,safe=False)
else:
return render_to_response('AjaxDemo.html',context_instance=RequestContext(request))
需要注意：
(1)在使用引入的JS代码后，需要添加如下代码，这样JS就可以自动帮我们生成"csrfmiddlewaretoken"标识,接下来你就可以使用$.post()了
$.ajaxSetup({
data:{csrfmiddlewaretoken: '{{ csrf_token }}'}
});
(2)context_instance=RequestContext(request) 并不是必须的
(3)Get请求不需要以上操作，直接使用$.get()即可
总结：本人学习Django的时间不长，写博客的目的只要是为了自己做知识记录和对知识的分享，如果哪里写的不好，还请广大博友指点，多多包涵。