fix null json payload in net47 (#7870)

Author: wing328

modules/openapi-generator/src/main/resources/csharp-netcore/modelAnyOf.mustache

@@ -99,6 +99,11 @@
         public static {{classname}} FromJson(string jsonString)
         {
             {{classname}} new{{classname}} = null;
+
+            if (jsonString == null)
+            {
+                return new{{classname}};
+            }
             {{#anyOf}}
 
             try

modules/openapi-generator/src/main/resources/csharp-netcore/modelOneOf.mustache

@@ -99,6 +99,11 @@
         public static {{classname}} FromJson(string jsonString)
         {
             {{classname}} new{{classname}} = null;
+
+            if (jsonString == null)
+            {
+                return new{{classname}};
+            }
             {{#useOneOfDiscriminatorLookup}}
             {{#discriminator}}
 

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/Fruit.cs

@@ -137,6 +137,11 @@ public override string ToJson()
         public static Fruit FromJson(string jsonString)
         {
             Fruit newFruit = null;
+
+            if (jsonString == null)
+            {
+                return newFruit;
+            }
             int match = 0;
             List<string> matchedTypes = new List<string>();
 

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/FruitReq.cs

@@ -146,6 +146,11 @@ public override string ToJson()
         public static FruitReq FromJson(string jsonString)
         {
             FruitReq newFruitReq = null;
+
+            if (jsonString == null)
+            {
+                return newFruitReq;
+            }
             int match = 0;
             List<string> matchedTypes = new List<string>();
 

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/GmFruit.cs

@@ -137,6 +137,11 @@ public static GmFruit FromJson(string jsonString)
         {
             GmFruit newGmFruit = null;
 
+            if (jsonString == null)
+            {
+                return newGmFruit;
+            }
+
             try
             {
                 newGmFruit = new GmFruit(JsonConvert.DeserializeObject<Apple>(jsonString, GmFruit.SerializerSettings));

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/Mammal.cs

@@ -165,6 +165,11 @@ public static Mammal FromJson(string jsonString)
         {
             Mammal newMammal = null;
 
+            if (jsonString == null)
+            {
+                return newMammal;
+            }
+
             string discriminatorValue = JObject.Parse(jsonString)["className"].ToString();
             switch (discriminatorValue)
             {

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/NullableShape.cs

@@ -148,6 +148,11 @@ public static NullableShape FromJson(string jsonString)
         {
             NullableShape newNullableShape = null;
 
+            if (jsonString == null)
+            {
+                return newNullableShape;
+            }
+
             string discriminatorValue = JObject.Parse(jsonString)["shapeType"].ToString();
             switch (discriminatorValue)
             {

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/Pig.cs

@@ -139,6 +139,11 @@ public static Pig FromJson(string jsonString)
         {
             Pig newPig = null;
 
+            if (jsonString == null)
+            {
+                return newPig;
+            }
+
             string discriminatorValue = JObject.Parse(jsonString)["className"].ToString();
             switch (discriminatorValue)
             {

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/Quadrilateral.cs

@@ -139,6 +139,11 @@ public static Quadrilateral FromJson(string jsonString)
         {
             Quadrilateral newQuadrilateral = null;
 
+            if (jsonString == null)
+            {
+                return newQuadrilateral;
+            }
+
             string discriminatorValue = JObject.Parse(jsonString)["quadrilateralType"].ToString();
             switch (discriminatorValue)
             {

samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Model/Shape.cs

@@ -139,6 +139,11 @@ public static Shape FromJson(string jsonString)
         {
             Shape newShape = null;
 
+            if (jsonString == null)
+            {
+                return newShape;
+            }
+
             string discriminatorValue = JObject.Parse(jsonString)["shapeType"].ToString();
             switch (discriminatorValue)
             {