Function getDataFromBase64String

获取dataUrl中的信息

getDataFromBase64String("data:image/png;base64,base64Content") 
// 返回 
{ isMatch: true, dataType: "image", dataSuffix: "png", mime: "image/png", dataData: "base64Content", additionalInfo:""  }  
// -- 
getDataFromBase64String("data:;base64,remain+text") 
// 返回 
{ isMatch: true, dataType: "", dataSuffix: "", mime: "/", dataData: "remain+text", additionalInfo:""  }  
// -- 
getDataFromBase64String("data:,remain+text") 
// 返回 
{ isMatch: true, dataType: "", dataSuffix: "", mime: "/", dataData: "remain+text" }
// -- 
getDataFromBase64String("data:image/png;fileName=b.png,c=8&d=9,base64,remain+text") 
// 返回 
{ isMatch: true, dataType: "", dataSuffix: "", mime: "/", dataData: "remain+text", additionalInfo:"" }  
// -- 
getDataFromBase64String("data:image/png;fileName=b.png,c=8&d=9,type=base64,base64,remain+text") 
// 返回 
{ isMatch: true, dataType: "image", dataSuffix: "png", mime: "image/png", dataData: "remain+text",additionalInfo: "fileName=b.png,c=8&d=9,type=base64," }  

Returns