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Somehow i cannot get any result from my backend solidity. i have asimple dapp that takes firstName from input field save in blockchain and then fetch it back and display it on the screen.

state={

fName:"",
firstName:"",

}


handleSubmit = async (event)=>{
    event.preventDefault();
    await this.simpleStorageInstance.set(this.state.fName, { from: this.state.account });
    //let name = this.simpleStorageInstance.get.call(this.state.account);

    this.simpleStorageInstance.get({ from: this.state.account }, function (error, result) {
        var name = result;
        this.setState({ firstName: name });


    })

doChange = (e)=>{
this.setState({fName:e.target.value});

}

render(<div> <form onSubmit={this.handleSubmit}>

<input type="text" name="firsName" onChange={this.doChange}/>
<input type="submit"/></form>

<p>{this.state.firstName}</p></div>);

pragma solidity 0.4.24;

contract SimpleStorage {
    string firstName;

    function set(string x) public {
        firstName = x;
    }

    function get() public view returns (string) {
        return firstName;
    }
}

I get also this error:

Uncaught (in promise) Error: Invalid number of arguments to Solidity function at Object.InvalidNumberOfSolidityArgs (errors.js:25) at SolidityFunction../node_modules/web3/lib/web3/function.js.SolidityFunction.validateArgs (function.js:74) at SolidityFunction../node_modules/web3/lib/web3/function.js.SolidityFunction.toPayload (function.js:90) at SolidityFunction../node_modules/web3/lib/web3/function.js.SolidityFunction.call (function.js:131) at contract.js:135 at new Promise () at contract.js:126

0
this.simpleStorageInstance.get({ from: this.state.account }

There is no need to pass { from: this.state.account } this while calling a get function.

Refer to this tutorial to understand the difference between read-only calls and potentially state-changing transactions.

Refer to this tutorial in which similar example as you are trying to develop is explained.

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