Json.Net使用JSON Schema验证JSON格式【实例】
给出一个Json，验证其格式是否符合规则。
{ "coord": { //对象 "lon": 145.77, "lat": -16.92 }, "sys": { //对象 "type": 1, "id": 8166, "message": 0.0402, "country": "AU", "sunrise": 1417116823, "sunset": 1417163764 }, "weather": [ //数组（子项是对象） { "id": 801, "main": "Clouds", "description": "few clouds", "icon": "02d" }, { "id": 801, "main": "Clouds", "description": "few clouds", "icon": "02d" } ], "base": "cmc stations", //字符串 "main": { //对象 "temp": 304.15, //浮点型 "pressure": 1012, //整形 "humidity": 43, //整形 "temp_min": 304.15, "temp_max": 304.15 }, "wind": { //对象 "speed": 5.7, "deg": 110 }, "clouds": { "all": 20 }, "dt": 1417134600, //整形 "id": 2172797, //整形 "name": "Cairns", //字符串 "cod": 200 //整形 }
在前一篇文中我们知道JSON Schema可以通过加载字符串或者文件得到，可是新手一下子写出验证的字符串实在有点难度。
还好，Json.Net里面可以在代码里创建JSON Schema，简直是手把手教学，显浅易懂。
参见上一篇文中的代码里创建JSON Schema，我们将这个Json分拆为coord、sys、weather、base、main、wind、clouds、dt等等小的json，逐一创建对应的模式，最后组合在一起验证完整的Json。
JsonSchema coordSchema = new JsonSchema(); coordSchema.Type = JsonSchemaType.Object; coordSchema.Properties = new Dictionary<string, JsonSchema> { { "lon", new JsonSchema { Type = JsonSchemaType.Float } }, { "lat", new JsonSchema { Type = JsonSchemaType.Float } } }; JsonSchema sysSchema = new JsonSchema(); sysSchema.Type = JsonSchemaType.Object; sysSchema.Properties = new Dictionary<string, JsonSchema> { { "type", new JsonSchema { Type = JsonSchemaType.Integer } }, { "id", new JsonSchema { Type = JsonSchemaType.Integer } }, { "message", new JsonSchema { Type = JsonSchemaType.Float } }, { "country", new JsonSchema { Type = JsonSchemaType.String } }, { "sunrise", new JsonSchema { Type = JsonSchemaType.Integer } }, { "sunset", new JsonSchema { Type = JsonSchemaType.Integer } } }; JsonSchema weatherItemSchema = new JsonSchema(); weatherItemSchema.Type = JsonSchemaType.Object; weatherItemSchema.Properties = new Dictionary<string, JsonSchema> { { "id", new JsonSchema { Type = JsonSchemaType.Integer } }, { "main", new JsonSchema { Type = JsonSchemaType.String } }, { "description", new JsonSchema { Type = JsonSchemaType.String } }, { "icon", new JsonSchema { Type = JsonSchemaType.String } } }; JsonSchema windSchema = new JsonSchema(); windSchema.Type = JsonSchemaType.Object; windSchema.Properties = new Dictionary<string, JsonSchema> { { "speed", new JsonSchema { Type = JsonSchemaType.Float } }, { "deg", new JsonSchema { Type = JsonSchemaType.Integer } } }; JsonSchema weatherSchema = new JsonSchema(); weatherSchema.Type = JsonSchemaType.Array; weatherSchema.Items = new List<JsonSchema>(); weatherSchema.Items.Add(weatherItemSchema); JsonSchema mainSchema = new JsonSchema(); mainSchema.Type = JsonSchemaType.Object; mainSchema.Properties = new Dictionary<string, JsonSchema> { { "temp", new JsonSchema { Type = JsonSchemaType.Float } }, { "pressure", new JsonSchema { Type = JsonSchemaType.Integer } }, { "humidity", new JsonSchema { Type = JsonSchemaType.Integer } }, { "temp_min", new JsonSchema { Type = JsonSchemaType.Float } }, { "temp_max", new JsonSchema { Type = JsonSchemaType.Float } } }; JsonSchema cloudsSchema = new JsonSchema(); cloudsSchema.Type = JsonSchemaType.Object; cloudsSchema.Properties = new Dictionary<string, JsonSchema> { { "all", new JsonSchema { Type = JsonSchemaType.Float } } };
最后将这些分支的模式组合起来：
JsonSchema schema = new JsonSchema(); schema.Type = JsonSchemaType.Object; schema.Properties = new Dictionary<string, JsonSchema> { {"coord", coordSchema }, {"sys", sysSchema }, {"weather",weatherSchema}, {"base", new JsonSchema{Type = JsonSchemaType.String} }, {"main",mainSchema}, {"wind",windSchema}, {"clouds",cloudsSchema}, {"dt", new JsonSchema{Type = JsonSchemaType.Integer} }, {"id", new JsonSchema{Type = JsonSchemaType.Integer} }, {"name", new JsonSchema{Type = JsonSchemaType.String} }, {"cod", new JsonSchema{Type = JsonSchemaType.Integer} } }; bool valid = jobject.IsValid(schema);
也可以将最后的schema转化为字符串保存在专门的文件里，需要的时候从中读取：
{ "type": "object", "properties": { "coord": { "type": "object", "properties": { "lon": { "type": "number" }, "lat": { "type": "number" } } }, "sys": { "type": "object", "properties": { "type": { "type": "integer" }, "id": { "type": "integer" }, "message": { "type": "number" }, "country": { "type": "string" }, "sunrise": { "type": "integer" }, "sunset": { "type": "integer" } } }, "weather": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "integer" }, "main": { "type": "string" }, "description": { "type": "string" }, "icon": { "type": "string" } } } }, "base": { "type": "string" }, "main": { "type": "object", "properties": { "temp": { "type": "number" }, "pressure": { "type": "integer" }, "humidity": { "type": "integer" }, "temp_min": { "type": "number" }, "temp_max": { "type": "number" } } }, "wind": { "type": "object", "properties": { "speed": { "type": "number" }, "deg": { "type": "integer" } } }, "clouds": { "type": "object", "properties": { "all": { "type": "number" } } }, "dt": { "type": "integer" }, "id": { "type": "integer" }, "name": { "type": "string" }, "cod": { "type": "integer" } } }
验证说明：
1、原Json字符串，正确；
2、原Json的weather列表增加{"id": 801,"main": "Clouds","description": "few clouds","icon": "02d"}，正确；
3、原Json的id修改为haha，错误；
4、原Json增加"planet":earth，错误，增加了额外的结构；
5、原Json删除"id": 2172797, "cod": 200，正确