I have the following JSON structure, calling it from web:
[
{
"Code":"31212",
"Desc":"JOHN",
"DOYDESC":"MADRID",
"Street":"Str41",
"StreetNo":"86"
},
{
"Code":"30214",
"Desc":"GEORGE",
"DOYDESC":"NEW YORK",
"Street":"Str3",
"StreetNo":null
},
{
"Code":"09215",
"Desc":"MARY",
"DOYDESC":"PARIS",
"Street":"Str3",
"StreetNo":"22"
},
{
"Code":"10217",
"Desc":"MEGAN",
"DOYDESC":"ROME",
"Street":"Str4",
"StreetNo":null
}
]
I want the user to give a number in Edit.Text
, and then search the values of Code
to find if the given value exists.
Is there a way to create an array named Code
with the values from the JSON?
For example, to create something like this:
Code = ["31212","30214","09215","10217"]
and then make the search? Or, is there another way to find a specific value of Code
from the JSON? I tried this so far:
procedure Tlog_form.Button2Click(Sender: TObject);
var
jso : TJsonObject;
jsv,jsval : TJsonValue;
jsa,jsarr : TJsonArray;
data,str : string;
i,j,user : integer;
jsp : TJsonPair;
arr : array of string;
begin
try
data := GetURLAsString('http://...');
except
on E: exception do
end;
try
jsv := TJSONObject.ParseJSONValue(data);
try
jsa := jsv as TJSONArray;
try
for I := 0 to jsa.Size - 1 do
begin
jso := jsa.Get(i) as TJsonObject;
if jso.ToString = 'Code' then
begin
str := jso.GetValue('Code').ToString;
if Edit1.Text = str then
begin
ShowMessage('found it');
end;
end;
end;
finally
end;
finally
jsv.Free;
end;
except
on E: exception do
end;
end;
When I debug, it doesn't get any error. but it still doesn't work.
CodePudding user response:
You are converting each TJSONObject
in the array to a string
, and then comparing that to your TEdit
text. Which will obviously not match. You need to compare only the Code
field of each TJSONObject
, which you would be doing if you remove the if jso.ToString = 'Code' then
check completely, eg:
procedure Tlog_form.Button2Click(Sender: TObject);
var
jsv : TJSONValue;
jsa : TJSONArray;
jso : TJSONObject;
data, str, code : string;
I : integer;
begin
str := Edit1.Text;
try
data := GetURLAsString('http://...');
jsv := TJSONObject.ParseJSONValue(data);
if jsv <> nil then
try
jsa := jsv as TJSONArray;
for I := 0 to jsa.Size - 1 do
begin
jso := jsa.Get(I) as TJSONObject;
code := jso.GetValue('Code').ToString;
if str = code then
begin
ShowMessage('found it');
end;
end;
finally
jsv.Free;
end;
except
end;
end;
CodePudding user response:
I'm not sure I understand you very well, but if you try TALJsonDocument
(https://github.com/Zeus64/alcinoe), you have this function:
Function ALFindJsonNodeByTextChildNodeValue(const JsonNode:TalJsonNode;
Const ChildNodeName: AnsiString;
Const ChildNodeValue : AnsiString;
Const Recurse: Boolean = False): TALJsonNode;