Shale gas horizontal well full-life-cycle drainage and gas production integrated string and construction method

The invention provides a shale gas horizontal well full-life-cycle drainage and gas production integrated string and a construction method. The string comprises an oil pipe, a casing pipe and a tail pipe, the top end of the oil pipe is hung in the casing pipe through an oil pipe hanger, a plurality of eccentric gas lift valves are arranged on the oil pipe at intervals, and the lower middle portionof the oil pipe is connected with a plunger limiting short section. The bottom end of the oil pipe is connected with the top of a direct-circulation injection pump, the bottom of the direct-circulation injection pump is connected with the top end of the tail pipe, the casing pipe sleeves the oil pipe and the tail pipe and is centrally aligned, and a packer is arranged in an annulus, correspondingto the casing pipe, of the upper portion of the tail pipe. Gas well drainage and gas production processes of optimized strings, gas lift valves and plungers are integrated, process switching and connection are completed throu