如何使用Wasm-Bindgen Web_sys Wasm-pack将字符串从Js传递到Wasm

Question

代码是基本的，我从js调用一个函数，在lib.rs中声明了一个字符串输入，但字符串没有传递给wasm中的函数，我收到了一个空字符串，反之也不起作用，我也不能将字符串从wasm传递给js。

wasm文件如下所示

use wasm_bindgen::prelude::*;
use web_sys::console;

// When the `wee_alloc` feature is enabled, use `wee_alloc` as the global
// allocator.
#[cfg(feature = "wee_alloc")]
#[global_allocator]
static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;

#[wasm_bindgen]
pub fn hello(v: String) {
    console::log_1(&v.into()); //prints => empty string
}

js看起来这个wasm已经成功初始化了，其他函数运行正常。

wasm.hello("hello")

cargo toml看起来像这样

[package]
name = "painter"
version = "0.1.0"
edition = "2018"

[lib]
crate-type = ["cdylib", "rlib"]

[features]
default = ["console_error_panic_hook"]

[dependencies]
wasm-bindgen = "0.2"
#web-sys = "0.3.39"

# The `console_error_panic_hook` crate provides better debugging of panics by
# logging them with `console.error`. This is great for development, but requires
# all the `std::fmt` and `std::panicking` infrastructure, so isn't great for
# code size when deploying.
console_error_panic_hook = { version = "0.1.1", optional = true }

[dependencies.web-sys]
version = "0.3.39"
features = [
  "console",
  "Document",
  "Element",
  "HtmlElement",
  "Node",
  "Window"
 ]  # Do you have this line in your Cargo.toml?

# `wee_alloc` is a tiny allocator for wasm that is only ~1K in code size
# compared to the default allocator's ~10K. It is slower than the default
# allocator, however.
#
# Unfortunately, `wee_alloc` requires nightly Rust when targeting wasm for now.
wee_alloc = { version = "0.4.2", optional = true }

[dev-dependencies]
wasm-bindgen-test = "0.2"

[profile.release]
# Tell `rustc` to optimize for small code size.
opt-level = "s"

Answer 1

我已经弄清楚了，我使用的是wasm init的导出，而不是通过wasm-pack生成的js文件的导出，所以在使用wasm-pack导出时请记住这一点，并在启动js文件之后使用它。