Menu
how can I "convert" a Cursor to a JSONArray?
my cursor as 3columns (_id, name, birth)
I've searched but I can't not find any examples
752
What is JsonResult ? JsonResult is one of the type of MVC action result type which returns the data back to the view or the browser in the form of JSON (JavaScript Object notation format). In this article we will learn about JsonResult by taking scenario to bind view using the JSON Data .
MySQL supports the native JSON data type since version 5.7. 8. The native JSON data type allows you to store JSON documents more efficiently than the JSON text format in the previous versions. MySQL stores JSON documents in an internal format that allows quick read access to document elements.
How to Retrieve data from JSON column in MySQL. MySQL provides two operators ( -> and ->> ) to extract data from JSON columns. ->> will get the string value while -> will fetch value without quotes. As you can see ->> returns output as quoted strings, while -> returns values as they are.
JSON columns, like columns of other binary types, are not indexed directly; instead, you can create an index on a generated column that extracts a scalar value from the JSON column. See Indexing a Generated Column to Provide a JSON Column Index, for a detailed example.
private String cursorToString(Cursor crs) {
JSONArray arr = new JSONArray();
crs.moveToFirst();
while (!crs.isAfterLast()) {
int nColumns = crs.getColumnCount();
JSONObject row = new JSONObject();
for (int i = 0 ; i < nColumns ; i++) {
String colName = crs.getColumnName(i);
if (colName != null) {
String val = "";
try {
switch (crs.getType(i)) {
case Cursor.FIELD_TYPE_BLOB : row.put(colName, crs.getBlob(i).toString()); break;
case Cursor.FIELD_TYPE_FLOAT : row.put(colName, crs.getDouble(i)) ; break;
case Cursor.FIELD_TYPE_INTEGER: row.put(colName, crs.getLong(i)) ; break;
case Cursor.FIELD_TYPE_NULL : row.put(colName, null) ; break;
case Cursor.FIELD_TYPE_STRING : row.put(colName, crs.getString(i)) ; break;
}
} catch (JSONException e) {
}
}
}
arr.put(row);
if (!crs.moveToNext())
break;
}
crs.close(); // close the cursor
return arr.toString();
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
