使用Json.Net序列化模型时自动使用HtmlEncode字符串

Question

是否有一种方法可以将Json.Net配置为在序列化模型时自动编码所有字符串，如HtmlEncode(myString) ？

Answer 1

您可以使用类似于反序列化期间在字符串中选择性地转义HTML的解决方案，并进行一些小的更改：

1. 更改HtmlEncodingValueProvider以在GetValue而不是SetValue应用编码（以便它在序列化而不是反序列化时执行编码）。
2. 更改解析程序以将值提供程序应用于所有字符串属性，而不是查找属性。

以下是生成的代码的样子：

public class CustomResolver : DefaultContractResolver
{
    protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)
    {
        IList<JsonProperty> props = base.CreateProperties(type, memberSerialization);

        // Attach an HtmlEncodingValueProvider instance to all string properties
        foreach (JsonProperty prop in props.Where(p => p.PropertyType == typeof(string)))
        {
            PropertyInfo pi = type.GetProperty(prop.UnderlyingName);
            if (pi != null)
            {
                prop.ValueProvider = new HtmlEncodingValueProvider(pi);
            }
        }

        return props;
    }

    protected class HtmlEncodingValueProvider : IValueProvider
    {
        PropertyInfo targetProperty;

        public HtmlEncodingValueProvider(PropertyInfo targetProperty)
        {
            this.targetProperty = targetProperty;
        }

        // SetValue gets called by Json.Net during deserialization.
        // The value parameter has the original value read from the JSON;
        // target is the object on which to set the value.
        public void SetValue(object target, object value)
        {
            targetProperty.SetValue(target, (string)value);
        }

        // GetValue is called by Json.Net during serialization.
        // The target parameter has the object from which to read the string;
        // the return value is the string that gets written to the JSON
        public object GetValue(object target)
        {
            string value = (string)targetProperty.GetValue(target);
            return System.Web.HttpUtility.HtmlEncode(value);
        }
    }
}

像这样使用自定义ContractResolver ：

var settings = new JsonSerializerSettings
{
    ContractResolver = new CustomResolver(),
    Formatting = Formatting.Indented
};

string json = JsonConvert.SerializeObject(your_object, settings);

小提琴： https ： //dotnetfiddle.net/RhFlk8

Answer 2

尝试这个：

var json = JObject.Parse("{'Name':'<script>alert(1);</script>'}");
var serializerSettings = new JsonSerializerSettings()
{
    StringEscapeHandling = StringEscapeHandling.EscapeHtml
};
var result = JsonConvert.SerializeObject(json, serializerSettings);

结果将是：

{"Name":"\u003cscript\u003ealert(1);\u003c/script\u003e"}

Answer 3

我发现了一个非常简单的方法（WebAPI2）。

设置对象属性时，只需使用下面的代码进行编码即可。

myObject.encoded_field = HttpUtility.HtmlEncode（your_html_content）