React对fetch的简单封装

import {getStrValue, isObjNull} from "./common";

export function fetchPost(url, params, header) {
    if (isObjNull(header)) {
        header = {}
    }

    let formData = new FormData()
    if (params) {
        for (let key in params) {
            // if ((typeof params[key]) === 'string') {
            //     formData.append(key, encodeURI(params[key].toString()))
            // } else {
            formData.append(key, params[key])
            // }
        }
    }

    const request = fetch(url, {
        method: 'POST',
        body: formData,
        mode: 'cors',
        // credentials: 'include',
        // cache: "force-cache",
        headers: new Headers({
            'Accept': 'application/json',
            // "Content-Type": "application/x-www-form-urlencoded; charset=utf-8",
            ...header
        })
    })

    return fetchResult(request)
}

export function fetchGet(url, params, header) {
    if (isObjNull(header)) {
        header = {}
    }

    if (params) {
        let paramsArray = [];
        //拼接参数
        Object.keys(params).forEach(key =>
            paramsArray.push(key + '=' + encodeURI(getStrValue(params, key).toString())))

        if (paramsArray.length > 0) {
            if (url.search(/\?/) === -1) {
                url += '?' + paramsArray.join('&')
            } else {
                url += '&' + paramsArray.join('&')
            }
        }
    }

    const request = fetch(url, {
        method: 'GET',
        mode: 'cors',
        // credentials: 'include',
        // cache: "force-cache",
        headers: new Headers({
            'Accept': 'application/json',
            "Content-Type": "application/x-www-form-urlencoded; charset=utf-8",
            ...header
        })
    })

    return fetchResult(request)
}

/**
 * 处理网络请求结果
 * @param request
 * @returns {*}
 */
function fetchResult(request) {
    try {
        return request.then(response => {
            if (response.status == 200) {
                return response;
            } else {
                throw response
            }
        }).catch(error => {
            if (error.json) {
                return error.json()
            } else {
                return Promise.reject('请求异常')
            }
        }).then(result => {
            if (result.status == 200) {
                let resultJson = result.json();
                return resultJson;
            } else {
                if (result.exceptionInfo) {
                    if (result.exceptionInfo.length > 30) {
                        throw '接口请求异常'
                    } else {
                        throw result.exceptionInfo
                    }
                } else {
                    throw result
                }
            }
        }).then(result => {
            console.log(result)
            if (result.success) {
                return result
            } else {
                if (result.exceptionInfo) {
                    if (result.exceptionInfo.length > 30) {
                        throw '接口请求异常'
                    } else {
                        throw result.exceptionInfo
                    }
                } else if (result.message) {
                    if (result.message.length > 30) {
                        throw '接口请求异常'
                    } else {
                        throw result.message
                    }
                } else {
                    throw result
                }
            }
        })
    } catch (e) {
        return Promise.reject('请求异常')
    }

}