import { Observable } from 'rxjs';
import { SheetModel } from './sheet-model';
import { SheetReadResult } from './sheet-read-result';
export declare class NecSheetService {
    constructor();
    /**
     * 导出excel
     */
    exportExcel(excelModel: SheetModel, type: any, fileName: string, cellMerges?: any): void;
    exportMultipleExcel(excelModels: SheetModel[], type: any, fileName: string, cellMerges?: any, columnWidth?: number): void;
    /**
     * 判断是否excel文件
     */
    isExcel(file: File): boolean;
    /**
     * 将指定的自然数转换为26进制表示。映射关系：[0-25] -> [A-Z]
     */
    private getCharCol;
    private getColsWidth;
    /**
     * 字符串转字符流
     */
    private s2ab;
    readXLSX(file: any): Observable<SheetReadResult>;
}