Get one param of input body.

@param string $key

@return mixed
435072
public function getBodyParam($key, $default = null)
    {
        $params = $this->getBodyParams();
        if (array_key_exists($key, $params)) {
            return $params[$key];
        }
        return $default;
    }
74589
public static function param($key = ''){
		if($key){
			$get = self::get();
			$post = self::post();
			if(isset($post[$key])){
				return $post[$key] ;
			}else if(isset($get[$key])){
				return $get[$key] ;
			}else{
				return "";
			}
		}else{
			$get = self::get();
			$post = self::post();
			return array_merge($get,$post);
		}
	}
1099319
protected function getAsString($key)
    {
        $this->checkForNonEmptyKey($key);

        return trim((string)$this->get($key));
    }
503285
public function getParameter($key)
    {
        $filteredParameters = $this->parameters->filter(
            function ($parameter) use ($key)
            {
                // Must not be identical because of string to integer conversion
                return ($key == $parameter->getName());
            }
        );

        return count($filteredParameters) ? $filteredParameters->first() : null;
    }
1334829
public function offsetGet($key) {
		$key = strtolower($key);
		return isset($this->data[$key]) ? $this->data[$key] : null;
	}
39216
public function getParameter($key)
    {
        $query = $this->getQuery();

        return isset($query[$key]) ? $query[$key] : null;
    }
20749
public function getParameter($key)
    {
        $filteredParameters = $this->parameters->filter(
            static function (Query\Parameter $parameter) use ($key) : bool {
                $parameterName = $parameter->getName();

                return $key === $parameterName || (string) $key === (string) $parameterName;
            }
        );

        return $filteredParameters->isEmpty() ? null : $filteredParameters->first();
    }
365008
public function getParam($key)
    {
        if (method_exists($this, 'get'.$key)) {
            return $this->{'get'.$key}();
        }

        // always use uppercase
        $key = strtoupper($key);
        $parameters = array_change_key_case($this->parameters, CASE_UPPER);
        if (!array_key_exists($key, $parameters)) {
            throw new InvalidArgumentException('Parameter ' . $key . ' does not exist.');
        }

        return $parameters[$key];
    }
1278768
public static function &get($key)
    {
        self::startIf();
        if (isset($_SESSION[$key])) {
            return $_SESSION[$key];
        } else {
            $val = null;
            return $val;
        }
    }
535426
public function param($key, $default = null)
	{
		switch($this->paramIs($key))
		{
			case 'get'    : return $this->params_get->get($key);
			case 'post'   : return $this->params_post->get($key);
			case 'cookie' : return $this->cookies->get($key);
			case 'name'   : return $this->params_named->get($key);
		}

		return $default;
	}
679601
public function getParameter($key, $default = null) {
        $parameter = array_get($this->parameters, $key, $default);

        if ($parameter === null) {
            return $default;
        }

        return $parameter;
    }
44955
public function input($key = null, $default = null)
    {
        return $this->getParameter($key, $this->getPayloadData($key, $default));
    }
1217474
public function getParamByKey($key)
    {
        if (isset($this->extParams[$key]))
        {
            return $this->extParams[$key];
        }

        return null;
    }
716539
public function get($key)
    {
        $parts = explode('.', $key);
        $offset = $this->config;

        foreach($parts as $part) {
            if(!isset($offset[$part])) return null;

            $offset = $offset[$part];
        }

        return $offset;
    }
538182
public function getParam($key, $default = null)
    {
        $params = $this->params;
        if (is_array($params) && isset($params[$key])) {
            $result = $params[$key];
        } else {
            if (!is_string($default) && is_callable($default)) {
                $result = $default();
            } else {
                $result = $default;
            }
        }

        return $result;
    }
581479
public function getParam($key)
    {
        if (!isset($this->params[$key])) {
            throw new InvalidArgumentException("The request parameter with key '$key' is invalid."); 
        }
        return $this->params[$key];
    }
1303212
protected function getCurrentValue($key)
    {
        $key = $this->removeBrackets($key);

        if ($this->getConfig('method') === "GET" && $this->request->hasGet($key)) {
            return $this->request->get($key);
        }

        if ($this->getConfig('method') === "POST" && $this->request->hasPost($key)) {
            return $this->request->post($key);
        }

        if (!is_null($this->associatedEntity)) {
            $prefix = $this->keys['POST_WRAP'] . '.' . $this->associatedEntity->getInputName() . ".";
            $attributeName = str_replace($prefix, "", $key);
            if (isset($this->associatedEntity->{$attributeName})) {
                return $this->associatedEntity->{$attributeName};
            }
        }
    }