export class textFile
{
    /**保存单文件 text类型的 */
    static saveFile(filename: string, content: string)
    {
        let blob = new Blob([content], { type: "text/plain;charset=utf-8" });
        this.saveAs(filename, blob);
    }

    /**读取文件 选择文件组件,读取文档处理函数 */
    static readFile(eleFile, fn_doText, fileType = "", fn_msg = null)
    {
        let noEleFile = !(eleFile);
        if (noEleFile)
        {
            eleFile = document.createElement('input');
            eleFile.type = 'file';
            eleFile.accept = 'text/*';
            eleFile.hidden = true;
            document.body.appendChild(eleFile);
        }


        if (fileType && fileType != "") eleFile.accept = fileType;
        let reader = new FileReader();
        reader.onload = function (event)
        {
            let text = event.target["result"];
            if (fn_doText) fn_doText(text);
        };
        // 选择文件
        eleFile.onchange = function (event)
        {
            let file = event.target.files[0];
            if (file)
            {
                reader.readAsText(file);
            }
            if (fn_msg != null)
            {
                fn_msg();
            }
        };
        eleFile.click();

        if (noEleFile)
        {
            document.body.removeChild(eleFile);
        }

    }

    static getStringFromFile(eleFile, fileType = "", fn_msg = null): string
    {
        let noEleFile = !(eleFile);
        if (noEleFile)
        {
            eleFile = document.createElement('input');
            eleFile.type = 'file';
            eleFile.accept = 'text/*';
            eleFile.hidden = true;
            document.body.appendChild(eleFile);
        }


        if (fileType && fileType != "") eleFile.accept = fileType;
        let reader = new FileReader();
        reader.onload = function (event)
        {
            let text = event.target["result"];
            return text;
        };
        // 选择文件
        eleFile.onchange = function (event)
        {
            let file = event.target.files[0];
            if (file)
            {
                reader.readAsText(file);
            }
            if (fn_msg != null)
            {
                fn_msg();
            }
        };
        eleFile.click();

        if (noEleFile)
        {
            document.body.removeChild(eleFile);
        }
        return '';
    }
    /**保存文件 */
    static saveAs(fileName: string, data: Blob)
    {
        // 创建隐藏的可下载链接
        let eleLink = document.createElement('a');
        eleLink.download = fileName;
        eleLink.style.display = 'none';
        eleLink.href = URL.createObjectURL(data);
        // 触发点击
        document.body.appendChild(eleLink);
        eleLink.click();
        // 然后移除
        document.body.removeChild(eleLink);
    }

    static readFile2()
    {
        let rf = document.createElement('input');
        rf.type = 'file';
        rf.accept = 'text/*';
        rf.hidden = true;


        document.body.removeChild(rf);
    }

}