A television comprising: a display body comprising a shell and a main board , wherein the main board is provided with a first interface , the main board is installed in the shell , the shell is provided with a channel opening , and the channel opening is a channel for communicating an inside and an outside of the shell ; an interface extension apparatus installed in the shell , comprising a driving module and an interface extension line , wherein the interface extension line comprises a data line and a second interface , the second interface is a same type of data interface as the first interface , one end of the data line is connected with the first interface , and another end of the data line is connected with the second interface ; a line length detection module configured for detecting a first length information of the interface extension line located outside the shell and/or a second length information of the interface extension line located inside the shell ; the display body is also configured for displaying the first length information and/or the second length information; wherein the driving module is connected with the data line , the data line is wound directly or indirectly on an output shaft of the driving module , a rotation of the output shaft drives the data line connected to the driving module to increase or decrease a length wound on the output shaft, the driving module is configured for driving one end of the interface extension line provided with the second interface to extend out of the shell through the channel opening , and driving the interface extension line out of the shell to be retracted into the shell through the channel opening . a display body comprising a shell and a main board , wherein the main board is provided with a first interface , the main board is installed in the shell , the shell is provided with a channel opening , and the channel opening is a channel for communicating an inside and an outside of the shell ; an interface extension apparatus installed in the shell , comprising a driving module and an interface extension line , wherein the interface extension line comprises a data line and a second interface , the second interface is a same type of data interface as the first interface , one end of the data line is connected with the first interface , and another end of the data line is connected with the second interface ; a line length detection module configured for detecting a first length information of the interface extension line located outside the shell and/or a second length information of the interface extension line located inside the shell ; the display body is also configured for displaying the first length information and/or the second length information; wherein the driving module is connected with the data line , the data line is wound directly or indirectly on an output shaft of the driving module , a rotation of the output shaft drives the data line connected to the driving module to increase or decrease a length wound on the output shaft, the driving module is configured for driving one end of the interface extension line provided with the second interface to extend out of the shell through the channel opening , and driving the interface extension line out of the shell to be retracted into the shell through the channel opening . <EOS>