That's because coordinates is Object not Array , use for..in var coordinates = { "a": [ [1, 2], [8, 9], [3, 5], [6, 1] ], "b": [ [5, 8], [2, ... ... <看更多>

Running the latest SDK (1.8) with iPhone 5.0. Im creating a JSON-object from the server with php and json_encode. Here's the json-data which is returned in my ... ... <看更多>

TypeError: Cannot read property 'length' of undefined #424 ... at runPreParsing (\app\node_modules\fastify\lib\route.js:419:5) at Object. ... <看更多>

JavaScript undefined · What is undefined · 1) Accessing an uninitialized variable · 2) Accessing a non-existing property of an object · 3) Function parameters · 4) ... ... <看更多>

TypeError: Cannot read property 'length' of undefined ... _encodeMethodABI (/node_modules/web3-eth-contract/lib/index.js:438:8) at Object. ... <看更多>